Carbon reduction, nitrogen and phosphorus removal process of manganese oxide prepared by in-situ method in cooperation with MBBR (Moving Bed Biofilm Reactor)

Abstract

The invention discloses a carbon reduction, nitrogen and phosphorus removal process of manganese oxide prepared by an in-situ method in cooperation with an MBBR (moving bed biofilm reactor), and relates to the technical field of sewage treatment. The method comprises the following steps: preparing a required treatment system, and directionally domesticating activated sludge to prepare manganese-oxidizing mixed bacteria with Mn < 2 + > concentration of 2-5mg / L in supernate; the method comprises the following steps: starting an MBBR (Moving Bed Biofilm Reactor) in a biofilm formation manner, mixing sewage and a salt solution of Mn < 2 + >, introducing the mixture into the MBBR, enabling the added sewage of Mn < 2 + > to pass through a filler on which microorganisms and manganese oxides are grown in a process of flowing in the MBBR from bottom to top, and in the process, enabling the sewage to be in full contact with the filler loaded with the manganese oxides so as to perform carbon reduction, nitrogen removal and phosphorus removal. According to the method, Mn < 2 + > is added into the MBBR, so that manganese oxide can be generated in situ in the MBBR, full contact between the manganese oxide and sewage is realized in combination with an MBBR process, and the carbon reduction, nitrogen removal and phosphorus removal effects are improved.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a carbon reduction, nitrogen removal and phosphorus removal process of manganese oxide prepared in situ in coordination with an MBBR reactor. 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 shortage 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. In addition, due to the influence of various human activities, the phenomenon of eutrophication of water bodies and the coexistence of multiple pollutants is becoming more and more common. Usually, polluted water bodies contain eutrophic substances (such as nitrogen and phosphorus) and a large amount of difficult-to-degrade organic matter. These eutrophic substances and difficult-to-degrade organic matter continue to migrate and transform with the water flow, further infiltrate into the soil and even groundwater, posing a serious threat to human health and the water ecological 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, among many water treatment technologies, bioremediation technology that uses the metabolism of microorganisms to degrade pollutants and remove nitrogen and phosphorus is widely used. However, microorganisms are easily restricted by the growth environment, and the large amount of carbon sources such as methanol and acetic acid still have limitations such as high costs. In addition, the existing water treatment technology has high operating costs, occupies a large area, and is prone to secondary pollution.

[0004] In order to simultaneously achieve the treatment effect of removing nitrate and refractory organic matter, manganese oxide-mediated biological treatment technology has received increasing attention. By coupling denitrification with manganese redox cycle, the reaction rate of biological pathways can be increased, significantly reducing the demand for organic carbon by microorganisms. At the same time, manganese oxide can oxidize refractory organic matter to achieve the oxidation of organic pollutant ions or molecules into small molecules or ions, which are further degraded and utilized by microorganisms, allowing microorganisms to obtain energy and grow.

[0005] The research reports on manganese oxide-mediated microbial simultaneous denitrification and removal of organic pollutants in the prior art include:

[0006] Application No. 201210031269.7 discloses a method for the synergistic treatment of refractory micro-pollutants by natural manganese ore and microorganisms, which specifically comprises the following steps: the sewage is fed into the reactor from the bottom of the anaerobic bioreactor, and the sewage flows from bottom to top in the anaerobic bioreactor, passing through the natural manganese ore filler where a large number of microorganisms grow. In this process, the Mn in the natural manganese ore is 4+It is used as an electron acceptor, and the difficult-to-degrade micropollutants in the sewage are used as electron donors. Under the action of microorganisms (dissimilatory-Mn-reducing bacteria), electron transfer is promoted, so that the difficult-to-degrade micropollutants are degraded, and then the water is discharged from the top of the anaerobic bioreactor. Although this method uses an anaerobic bioreactor with natural manganese ore as a filling layer, it can effectively remove difficult-to-degrade organic pollutants in sewage, including persistent pollutants (POPs), precursors of trihalomethanes (THMFPs), endocrine disruptors (EDCs), and pharmaceuticals and personal care products (PPCPs). However, this method is to directly add natural manganese ore to form a natural manganese ore filling layer, and then contact with the sewage from bottom to top in the anaerobic bioreactor to degrade the pollutants in the sewage. The natural manganese ore filling layer has limited contact with the organic matter in the sewage, and the role of manganese oxide in the natural manganese ore filling cannot be fully utilized. In addition, the manganese oxide content in the natural manganese ore is low and the oxidation activity is limited. It is difficult to achieve a high activity state of newly formed manganese oxide, thereby failing to ensure the long-term and efficient removal of nitrates and difficult-to-degrade organic matter.

[0007] This shows that the prior art needs to be further improved. Summary of the invention

[0008] The object of the present invention is to provide a carbon reduction, nitrogen removal and phosphorus removal process for the coordinated use of manganese oxides prepared in situ in an MBBR reactor. By adding divalent manganese ions to the MBBR reactor, manganese oxides can be generated in situ in the MBBR reactor. Combined with the MBBR process, sufficient contact between manganese oxides and sewage is achieved, thereby improving the carbon reduction, nitrogen removal and phosphorus removal effects.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] A process for reducing carbon, nitrogen and phosphorus in a MBBR reactor using manganese oxide prepared in situ, comprising the following steps:

[0011] a. Prepare the required processing system

[0012] The treatment system includes an inlet tank, an MBBR reactor, a sedimentation tank and an outlet tank. The inlet tank is used to provide sewage and Mn to the MBBR reactor. 2+ The MBBR reactor is used to receive water from the lower side and discharge water from the upper side; the sedimentation tank is used to receive the effluent from the MBBR reactor; the filler in the MBBR reactor is a cylindrical porous polyethylene filler;

[0013] b. Preparation of manganese oxidizing mixed bacteria: Through targeted domestication of activated sludge, Mn in the supernatant was prepared. 2+ Mixed manganese-oxidizing bacteria at a concentration of 2 to 5 mg / L;

[0014] c. MBBR reactor biofilm start-up:

[0015] Initial biofilm formation: activated sludge and manganese oxidizing mixed bacteria are mixed in a mass ratio of 4 to 10:1 as inoculated sludge, and the inoculated sludge and sewage are mixed in a ratio of 1:1, and filled into the MBBR reactor to enter the anaerobic stage. After a certain period of anaerobic treatment, the inoculated sludge is emptied; this step is repeated to complete the initial biofilm formation;

[0016] Sewage and Mn 2+ The salt solution is mixed and enters the water inlet tank, and then enters the MBBR reactor from the outlet of the water inlet tank at a flow rate of 0.2-1.0 L / h. 10-30 mg of Mn is added to each 1 L of sewage. 2+ , each time water intake is 8 to 12 hours, and lasts for 5 to 10 days;

[0017] Sewage and Mn 2+ The salt solution is mixed and enters the water inlet tank, and then enters the MBBR reactor from the outlet of the water inlet tank at a flow rate of 0.5-2.0L / h. 10-30mg of Mn is added to each 1L of sewage. 2+ , the hydraulic retention time of the MBBR reactor is controlled to be 2 to 6 hours. After 5 to 7 days of operation, the effluent reaches a stable state; Mn 2+ In the MBBR reactor, it exists in the form of manganese oxide and is firmly loaded on the filler together with the microorganisms;

[0018] d. Wastewater and Mn 2+ After mixing with the salt solution, it is passed into the MBBR reactor. 20-50 mg of Mn is added to each liter of sewage. 2 + When the sewage flows from bottom to top in the MBBR reactor, it passes through the filler where microorganisms and manganese oxides grow. During this process, the sewage is fully in contact with the filler loaded with manganese oxides to reduce carbon, nitrogen and phosphorus.

[0019] e. When the Mn in the effluent of MBBR reactor 2+ When the mass content of Mn exceeds 50% of the influent, stop adding Mn 2+ The sewage is directly introduced into the MBBR reactor to reduce carbon, nitrogen and phosphorus.

[0020] The above-mentioned process for reducing carbon, nitrogen and phosphorus by cooperating with an MBBR reactor using manganese oxide prepared by an in-situ method, the MBBR reactor is a cylinder, the outside of the MBBR reactor is wrapped with tin foil, a porous partition is arranged 5 cm away from the bottom of the MBBR reactor, the diameter of the filler is 10 to 50 mm, the filler dosage rate is 70%, and the water distribution area is below the porous partition, and the water inlet of the MBBR reactor is located on the side wall of the water distribution area.

[0021] In the above-mentioned carbon reduction, nitrogen removal and phosphorus removal process of manganese oxide prepared by an in-situ method in coordination with an MBBR reactor, a water outlet is provided on the side wall 5 cm away from the top of the MBBR reactor, and the water outlet is connected to the water inlet of the sedimentation tank.

[0022] In the above-mentioned carbon reduction, nitrogen removal and phosphorus removal process of manganese oxide prepared by an in-situ method in cooperation with an MBBR reactor, in step b, the preparation steps of manganese oxidizing mixed bacteria are: adding glucose as a culture carrier to the sewage, adding 10 to 50 mg of glucose to each 1L of sewage; activated sludge as an inoculum; adding 10 to 30 mg / L of MnCl to the inoculum; 2 , cultured anaerobically at 35°C for 2-5 days until Mn 2+ Concentration is 10-20 mg / L;

[0023] Take the domesticated activated sludge as inoculum and repeat this step 2 to 5 times until Mn 2+ The concentration is 2 to 5 mg / L, and a manganese oxidizing mixed bacteria is obtained.

[0024] The above-mentioned in-situ prepared manganese oxide cooperates with the MBBR reactor to reduce carbon, nitrogen and phosphorus, Mn 2+ The salt solution is MnCl 2 Solution.

[0025] In the above-mentioned carbon reduction, nitrogen removal and phosphorus removal process of manganese oxide prepared by an in-situ method in coordination with an MBBR reactor, a conical sludge hopper is arranged inside the sedimentation tank, a sludge discharge port is provided below the sludge hopper, and the water outlet of the sedimentation tank is 5 cm away from the top.

[0026] In the above-mentioned carbon reduction, nitrogen removal and phosphorus removal process of manganese oxide prepared by an in-situ method in coordination with the MBBR reactor, the effluent in the sedimentation tank enters the effluent tank through the outlet.

[0027] The above-mentioned in-situ prepared manganese oxide cooperates with the MBBR reactor to reduce carbon, nitrogen and phosphorus, and the water inlet tank is connected to the sewage tank and Mn 2+ Reservoir tank.

[0028] The above-mentioned in-situ method of preparing manganese oxides is used in conjunction with the MBBR reactor to reduce carbon, nitrogen and phosphorus and degrade organic matter, and the application is the degradation of organic matter in rural sewage, sewage plant tail water or black and smelly water bodies.

[0029] Compared with the prior art, the present invention brings the following beneficial technical effects:

[0030] (1) The present invention proposes a carbon reduction, nitrogen removal and phosphorus removal process using manganese oxide prepared in situ in conjunction with an MBBR reactor. Unlike the prior art, the present invention does not directly add manganese oxide (manganese ore) into the reactor, but uses divalent manganese salt and microorganisms in the MBBR reactor to prepare manganese oxide in situ, that is, manganese redox reaction is achieved under biochemical action. It deeply removes organic matter from wastewater and simultaneously reduces carbon, nitrogen and phosphorus without causing secondary pollution. It is a green and low-carbon technology.

[0031] (2) The present invention uses cylindrical porous polyethylene fillers, which have a strong structure and a large effective specific surface area, making it easy for microorganisms and manganese oxide to attach.

[0032] (3) The present invention adopts a fluidized bed process to increase the contact between the functional filler and the wastewater, and the in-situ newly generated manganese oxide has a stronger oxidation ability, thereby enhancing the treatment effect.

[0033] (4) The present invention has low energy consumption and low water treatment cost, and can be applied to sewage plant tail water, rural sewage, black and smelly water bodies and other sewage containing difficult-to-degrade organic matter. Its COD, TN and TP removal rates can reach 70% to 90%, achieving deep removal of organic matter from sewage and simultaneous carbon reduction, nitrogen removal and phosphorus removal. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The present invention will be further described below in conjunction with the accompanying drawings:

[0035] Figure 1 This is a simplified structural diagram of the treatment system required for the carbon reduction, nitrogen removal and phosphorus removal process of manganese oxide prepared in situ by the present invention in cooperation with the MBBR reactor;

[0036] Figure 2 The COD inlet and outlet water concentration and removal rate change statistics of Example 1;

[0037] Figure 3 The TN inlet and outlet water concentration and removal rate change statistics of Example 1;

[0038] Figure 4 is NO of Example 1 3 - -N inlet and outlet water concentration and removal rate change statistics;

[0039] Figure 5 NH of Example 1 4 + -N inlet and outlet water concentration and removal rate change statistics;

[0040] Figure 6 This is a statistical chart of the changes in TP inlet and outlet water concentration and removal rate in Example 1.

[0041] In the figure:

[0042] 1. Pump, 2. Porous baffle, 3. Filler, 4. Exhaust pipe, 5. Valve, 6. Mud outlet, 7. Bell mouth, 8. Umbrella baffle, 9. Sewage tank, 10. Mn 2+ Liquid storage tank, 11. Water inlet tank, 12. MBBR reactor, 13. Sedimentation tank, 14. Water outlet tank. DETAILED DESCRIPTION

[0043] The present invention proposes a carbon reduction, nitrogen removal and phosphorus removal process of manganese oxide prepared in situ in cooperation with an MBBR reactor. 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.

[0044] The filler mentioned in the present invention is a porous polyethylene filler.

[0045] The Mn mentioned in the present invention 2+ The salt solution is MnCl 2 Solution.

[0046] like Figure 1 As shown, the treatment system required by the present invention includes an inlet box 11, an MBBR reactor 12, a sedimentation tank 13 and an outlet box 14, wherein the water inlet of the MBBR reactor 12 is at the lower side, the water inlet box is connected to the water inlet, and a pump 1 is arranged on the pipeline connecting the two; the water outlet of the MBBR reactor is at the upper side, and a valve 5 is installed on the outlet pipe arranged at the outlet. The outlet water of the MBBR reactor enters the sedimentation tank through the water inlet of the sedimentation tank, and the solid matter settles at the bottom of the sedimentation tank. The bottom of the water inlet pipe of the sedimentation tank is a bell mouth 7, and the bottom of the bell mouth is an umbrella-shaped baffle 8, and the clean water enters the outlet box through the outlet of the sedimentation tank. An exhaust port is arranged at the top of the MBBR reactor 12, and an exhaust pipe 4 is connected to the exhaust port.

[0047] Specifically, the inlet of the water inlet tank 11 is connected to the sewage tank 9, Mn 2+ The liquid storage tank 10 is connected to the sewage and Mn 2+ After mixing in the water inlet tank 11, the wastewater is sent to the MBBR reactor through the outlet of the water inlet tank. The wastewater can be sewage plant tail water, rural sewage, black and smelly water bodies and other wastewater containing difficult-to-degrade organic matter.

[0048] Specifically, the MBBR reactor is a cylinder, and the outside of the MBBR reactor is wrapped with tin foil. A porous partition 2 is set 5 cm from the bottom of the MBBR reactor. The diameter of the filler 3 is 10-50 mm, the porosity of the filler is greater than 95%, and the filler dosage rate is 70%. The water distribution area is below the porous partition, and the water inlet of the MBBR reactor is located on the side wall of the water distribution area. The height-to-diameter ratio of the MBBR reactor ranges from 3 to 5:1; the filler is a cylindrical porous polyethylene filler, the filler dosage rate (the ratio of the filler to the reactor volume) is 20% to 80%, and the residence time of sewage in the MBBR reactor is 2 to 24 hours.

[0049] Specifically, the height-to-diameter ratio of the sedimentation tank is in the range of 2 to 5:1, a conical sludge hopper is arranged below the sedimentation tank, the angle of the hypotenuse is 30° to 60°, a sludge discharge port 6 is arranged below the sludge hopper, and the hydraulic retention time of the sedimentation tank is 0.5 to 2 hours.

[0050] The difference between the present invention and the prior art is that it is not necessary to directly add manganese oxide to the reactor, but to allow Mn 2+ In the MBBR reactor, Mn 2+ Converted to Mn 4+ , and control Mn by effluent 2+ The dosage of .

[0051] In addition, the present invention uses manganese oxidizing mixed bacteria, which has better carbon reduction, nitrogen removal and phosphorus removal effects than pure bacteria in the prior art. For example, the pure bacteria in the prior art mainly remove certain specific organic matter and nitrogen, while the manganese oxidizing mixed bacteria of the present invention has a wider range of applications.

[0052] The preparation method of manganese oxidizing mixed bacteria is as follows: the mixed bacteria are obtained by directional domestication of activated sludge, using the untreated sewage with 10-50 mg / L glucose added as the culture carrier, the activated sludge as the inoculum (20%-50%, v / v), and adding 10-30 mg / L MnCl 2 , culture at 35℃ for 2-5 days with anaerobism and shaking, until the Mn(II) concentration in the supernatant is 10-20 mg / L. Take the domesticated activated sludge as inoculum and repeat the above steps 2-5 times, until the Mn(II) concentration in the supernatant is 2-5 mg / L, then the directional domestication is successful, and the manganese oxidizing mixed bacteria are obtained. Among them, the activated sludge includes but is not limited to denitrification sludge, sludge in the secondary sedimentation tank of the sewage plant, etc.

[0053] Before treating the sewage, the MBBR reactor needs to be started for biofilm growth. The specific method is as follows:

[0054] The first is the aeration stage, using activated sludge and manganese oxidizing mixed bacteria in a mass ratio of 4 to 10:1 as inoculated sludge, and the inoculated sludge and sewage in a mass ratio of 1:1 to fill the MBBR reactor. After 24 to 48 hours of aeration treatment, the sludge is emptied and filled with inoculated sludge again, and the operation is repeated for 5 to 15 days to complete the initial biofilm process.

[0055] Sewage and Mn 2+ After mixing with the salt solution, it enters the MBBR reactor at a low flow rate (0.2-1.0 L / h). 10-30 mg of Mn is added to each 1 L of sewage. 2+ , each time water intake is 8 to 12 hours, and lasts for 5 to 10 days.

[0056] Sewage and Mn 2+ After mixing with the salt solution, it enters the MBBR reactor at a large flow rate (0.5-2.0 L / h). 10-30 mg of Mn is added to each 1 L of sewage. 2+ , the hydraulic retention time of the MBBR reactor is controlled to be 2 to 6 hours. After 5 to 7 days of operation, the effluent reaches a stable state; Mn 2+ In the MBBR reactor, manganese exists in the form of manganese oxide and is firmly loaded on the filler with microorganisms, and the biofilm startup process is successfully completed.

[0057] The following is a detailed description of the carbon reduction, nitrogen removal and phosphorus removal process of manganese oxide prepared by an in-situ method in cooperation with an MBBR reactor of the present invention.

[0058] The specific steps include:

[0059] After the MBBR reactor is started, the sewage and Mn 2+ After mixing with the salt solution, it is passed into the MBBR reactor. 20-50 mg of Mn is added to each liter of sewage. 2+ When the sewage flows from bottom to top in the MBBR reactor, it passes through the filler where microorganisms and manganese oxides grow. During this process, the sewage is fully in contact with the filler loaded with manganese oxides to reduce carbon, nitrogen and phosphorus.

[0060] When the Mn 2+ When the mass content of Mn exceeds 50% of the influent, stop adding Mn 2+ The sewage is directly introduced into the MBBR reactor to reduce carbon, nitrogen and phosphorus.

[0061] Embodiment 1:

[0062] The phosphorus-containing water of the secondary effluent of a sewage treatment plant is taken as the research object, and the carbon reduction, nitrogen removal and phosphorus removal treatment is carried out in combination with the method of the present invention.

[0063] This embodiment provides a carbon reduction, nitrogen removal and phosphorus removal system of an in-situ manganese oxide MBBR reactor using the process. The system is set up using the treatment system of the present invention. The water pipe connection and the water flow direction are shown by arrows. The MBBR reactor set up in this embodiment is made of organic glass, with an inner diameter of 8 cm and a height of 40 cm. A porous partition is set 5 cm from the bottom to make the water distribution uniform and carry the porous polyethylene filler loaded with microorganisms and manganese oxides. The upper sampling port is 5 cm away from the top of the MBBR reactor.

[0064] The specific composition analysis of the experimental configuration water in the water inlet tank is shown in Table 1.

[0065] Table 1

[0066] Serial number Water quality indicators Concentration (mg / L) 1 TN 6～10 2 <![CDATA[NH 4 + -N]]> 0.3～0.8 3 <![CDATA[NO 3 - -N]]> 5～9 4 TP 1.2～1.5 5 COD 12～20 6 pH 6.5～7.5

[0067] The specific steps for building and starting the processing system of the present invention in this embodiment are as follows:

[0068] Step 1: Directed domestication of activated sludge from the secondary sedimentation tank of a sewage plant to prepare mixed manganese-oxidizing bacteria, using the treated sewage with 20 mg / L glucose as the culture carrier, activated sludge as the inoculum (1 L, 50%, v / v), and adding 15 mg / L MnCl 2 , cultured anaerobically at 35°C for 3 days until the Mn(II) concentration in the supernatant reached 10 mg / L. Take the domesticated activated sludge as inoculum and repeat the above steps 5 times until the Mn(II) concentration in the supernatant reached 2-5 mg / L to obtain manganese oxidizing mixed bacteria. Mix the manganese oxidizing mixed bacteria with the activated sludge from the secondary sedimentation tank of the sewage treatment plant in a ratio of 1:5 to obtain inoculum sludge;

[0069] Step 2: Fill a porous polyethylene filler with a diameter of 15 mm into an MBBR reactor with an inner diameter of 8 cm and a height of 40 cm at a filling rate of 70%;

[0070] Step 3: Inoculate the MBBR reactor with sludge, and start the in-situ manganese oxide MBBR reactor by aeration culture, with a small flow rate of 0.2L / h and a large flow rate of 0.5L / h, respectively, and the manganese oxide-microorganism fixation stage; the experimental water uses phosphorus-containing sewage prepared from the secondary effluent of a sewage plant. The preparation process is as follows: add a certain amount of pre-prepared inorganic salt solution to the secondary effluent of a sewage plant, stir the above liquid evenly, transfer the prepared water sample to the sewage tank, and use N 2 Aerate for 2 hours to reach anaerobic state;

[0071] Mn required to be added to the influent 2+ By adjusting Mn 2+ Pump flow control between reserve liquid and water inlet tank Mn 2+ Amount added;

[0072] Mn 2+ Mn in stock solution 2+ The concentration of MnCl was 200 mg / L. 2 Configuration, the configuration process is: add a certain amount of pre-prepared MnCl to tap water 2 After stirring the above liquid evenly, transfer the prepared solution to Mn 2+ The liquid tank is filled with N 2 Aerate for 2 hours to reach anaerobic state;

[0073] Step 4: After the in-situ manganese oxide MBBR reactor is successfully started, during the stable operation period, the experimental water in the water inlet tank is introduced into the MBBR reactor through a peristaltic pump, and it is continuously operated in a laboratory at 20-30°C with a hydraulic retention time of 12h;

[0074] Step 5: After the in-situ manganese oxide MBBR reactor is running stably, regularly monitor COD, TN, and NO 3 - -N, NH 4 + -N, TP and other pollutants as well as the carbon source utilization, organic matter removal rate, nitrogen removal efficiency and phosphorus removal efficiency of the MBBR reactor.

[0075] The results show that the in-situ manganese oxide MBBR reactor in this embodiment can achieve a COD removal rate of 80%, TN and NO 3 — The average removal rates of N and NH were 72.19% and 76.38%, respectively. 4 + -N removal rate is higher than 90%, TP removal rate is above 85%, combined with Figure 2 to Figure 6 It is shown that the in-situ manganese oxide MBBR reactor of this embodiment has excellent removal effect on various pollutants, and the manganese oxide prepared by the in-situ method provided by the present invention cooperates with the carbon reduction, nitrogen removal and phosphorus removal process of the MBBR reactor to achieve effective carbon reduction, nitrogen removal and phosphorus removal.

[0076] Parts not described in the present invention can be implemented by referring to the existing technology.

[0077] 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 process for carbon reduction, nitrogen removal and phosphorus removal using manganese oxide prepared in situ in cooperation with an MBBR reactor, characterized in that: The following steps are included in sequence: a. Prepare the required processing system The treatment system includes an inlet tank, an MBBR reactor, a sedimentation tank and an outlet tank. The inlet tank is used to provide sewage and Mn to the MBBR reactor. 2+ The MBBR reactor is used to receive water from the lower side and discharge water from the upper side; the sedimentation tank is used to receive the effluent from the MBBR reactor; the filler in the MBBR reactor is a cylindrical porous polyethylene filler; b. Preparation of manganese oxidizing mixed bacteria: Through targeted domestication of activated sludge, Mn in the supernatant was prepared. 2+ Mixed manganese-oxidizing bacteria at a concentration of 2 to 5 mg / L; c. Biofilm start-up of MBBR reactor: Initial biofilm formation: activated sludge and manganese oxidizing mixed bacteria are mixed in a mass ratio of 4 to 10:1 as inoculated sludge, and the inoculated sludge and sewage are mixed in a ratio of 1:1, and filled into the MBBR reactor to enter the anaerobic stage. After a certain period of anaerobic treatment, the inoculated sludge is emptied; this step is repeated to complete the initial biofilm formation; Sewage and Mn 2+ The salt solution is mixed and enters the water inlet tank, and then enters the MBBR reactor from the outlet of the water inlet tank at a flow rate of 0.2-1.0 L / h. 10-30 mg of Mn is added to each 1 L of sewage. 2+ , each time water intake is 8 to 12 hours, and lasts for 5 to 10 days; Sewage and Mn 2+ The salt solution is mixed and enters the water inlet tank, and then enters the MBBR reactor from the outlet of the water inlet tank at a flow rate of 0.5-2.0L / h. 10-30mg of Mn is added to each 1L of sewage. 2+ , the hydraulic retention time of the MBBR reactor is controlled to be 2 to 6 hours. After 5 to 7 days of operation, the effluent reaches a stable state; Mn 2+ In the MBBR reactor, it exists in the form of manganese oxide and is firmly loaded on the filler together with the microorganisms; d. Wastewater and Mn 2+ After mixing with the salt solution, it is passed into the MBBR reactor. 20-50 mg of Mn is added to each liter of sewage. 2+ When the sewage flows from bottom to top in the MBBR reactor, it passes through the filler where microorganisms and manganese oxides grow. During this process, the sewage is fully in contact with the filler loaded with manganese oxides to reduce carbon, nitrogen and phosphorus. e. When the Mn in the effluent of MBBR reactor 2+ When the mass content of Mn exceeds 50% of the influent, stop adding Mn 2+ The sewage is directly introduced into the MBBR reactor to reduce carbon, nitrogen and phosphorus.

2. The process for carbon reduction, nitrogen removal and phosphorus removal of manganese oxide prepared in situ according to claim 1 in cooperation with MBBR reactor, characterized in that: The MBBR reactor is a cylinder, and is wrapped with tin foil on the outside of the MBBR reactor. A porous partition is arranged 5 cm away from the bottom of the MBBR reactor. The diameter of the filler is 10 to 50 mm, and the filler dosage rate is 70%. The water distribution area is below the porous partition, and the water inlet of the MBBR reactor is located on the side wall of the water distribution area.

3. The carbon reduction, nitrogen removal and phosphorus removal process of the manganese oxide prepared in situ according to claim 2 in cooperation with the MBBR reactor is characterized in that: A water outlet is provided on the side wall 5 cm away from the top of the MBBR reactor, and the water outlet is connected to the water inlet of the sedimentation tank.

4. The process for carbon reduction, nitrogen removal and phosphorus removal by using manganese oxide prepared in situ in cooperation with MBBR reactor according to claim 1, characterized in that: In step b, the preparation steps of manganese oxidizing mixed bacteria are as follows: adding glucose as a culture carrier to sewage, adding 10 to 50 mg of glucose to each 1L of sewage; activated sludge as an inoculum; adding 10 to 30 mg / L of MnCl2 to the inoculum, and culturing anaerobically at 35°C for 2 to 5 days until Mn in the supernatant is reduced to 0. 2+ Concentration is 10-20 mg / L; Take the domesticated activated sludge as inoculum and repeat this step 2 to 5 times until Mn 2+ The concentration is 2 to 5 mg / L, and a manganese oxidizing mixed bacteria is obtained.

5. The process for carbon reduction, nitrogen removal and phosphorus removal of manganese oxide prepared in situ according to claim 1 in cooperation with MBBR reactor, characterized in that: Mn 2+ The salt solution is MnCl2 solution.

6. The process for carbon reduction, nitrogen removal and phosphorus removal in a MBBR reactor using manganese oxide prepared in situ according to claim 1, characterized in that: A conical sludge hopper is provided inside the sedimentation tank, and a sludge discharge port is provided below the sludge hopper. The water outlet of the sedimentation tank is 5 cm away from the top.

7. The process for carbon reduction, nitrogen removal and phosphorus removal in a MBBR reactor using manganese oxide prepared in situ according to claim 6, characterized in that: The water in the sedimentation tank enters the water outlet tank through the outlet.

8. The process for carbon reduction, nitrogen removal and phosphorus removal in a MBBR reactor using manganese oxide prepared in situ according to claim 1, characterized in that: The water inlet tank is connected to the sewage tank and Mn 2+ Reservoir tank.

9. The use of the manganese oxide prepared in situ according to any one of claims 1 to 8 in the carbon reduction, nitrogen removal and phosphorus removal process of the MBBR reactor in the degradation of organic matter, characterized in that: The application is the degradation of organic matter in rural sewage, sewage plant tail water or black and smelly water bodies.

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