Highway service area wastewater treatment method based on anaerobic ammonia oxidation enhanced AOOA-MBBR

Abstract

The invention relates to the field of expressway service area wastewater treatment, in particular to an expressway service area wastewater treatment method based on anaerobic ammonia oxidation enhanced AOOA-MBBR. The method comprises the following steps: 1, preparing a reactor; 2, starting the reactor and inoculating bacteria, and in the step, gradually shortening the hydraulic retention time to 20 hours after the effluent stably runs for a preset time; step 3, anaerobic ammonium oxidation strengthening: after the effluent stably runs for a preset time, respectively replacing part of filler in each tank by using filler of biofilm-forming anaerobic ammonium oxidation bacteria; the concentration of dissolved oxygen in the first aerobic tank is 0.2 mg / L, and the concentration of dissolved oxygen in the second aerobic tank is 0.5-0.8 mg / L; manganese sulfate is added into part of the wastewater of the highway service area, and then the wastewater is directly pumped into the second anoxic tank; and 4, after the effluent is stable, entering a stable stage. When the hydraulic retention time is 20 hours, the total nitrogen and total phosphorus of the effluent can reach corresponding emission standards, so that the wastewater treatment efficiency of the highway service area is improved, and the problem of trouble in subsequent phosphorus removal is avoided.

Description

Technical Field

[0001] The present invention relates to the field of wastewater treatment in highway service areas, and in particular to a method for treating wastewater in highway service areas based on anaerobic ammonia oxidation enhanced AOOA-MBBR. Background Art

[0002] Wastewater from highway service areas is mainly restaurant wastewater and fecal wastewater from public toilets, accounting for more than 85% of the total wastewater. The total nitrogen concentration in the wastewater is 2 to 3 times that of typical urban sewage, with high ammonia nitrogen concentration and very low carbon-nitrogen ratio, making denitrification very difficult.

[0003] In view of the high ammonia nitrogen concentration and low carbon-nitrogen ratio of highway service area wastewater, the inventor of this patent has previously applied for a patent with application number 202411483993.2, and the patent name is a highway service area wastewater treatment device and method based on AOOA-MBBR process. Denitrification and denitrification are achieved by culturing, domesticating, and enriching hydrolytic bacteria and denitrifying bacteria on the filler of the first anoxic tank, culturing, domesticating, and enriching hydrolytic bacteria, nitrifying bacteria, and denitrifying bacteria on the filler of the first aerobic tank to achieve simultaneous nitrification and denitrification, culturing, domesticating, and enriching nitrifying bacteria on the filler of the second aerobic tank to achieve nitrification of ammonia nitrogen in the effluent of the first aerobic tank, and culturing, domesticating, and enriching hydrolytic bacteria and denitrifying bacteria on the filler of the second anoxic tank to achieve denitrification and denitrification. When the hydraulic retention time of this method is 24h, the average concentration of total nitrogen in the treated effluent is 14.33mg / L, and the average removal rate is 90.49%. However, when the hydraulic retention time is reduced to 20 hours, it is difficult to reduce the total nitrogen in the effluent to below 15 mg / L, so the hydraulic retention time cannot be reduced further, resulting in low wastewater treatment efficiency. In addition, in this patent, phosphorus is hardly removed.

[0004] The wastewater from highway service areas generally refers to the Class A emission standard of the "Pollutant Discharge Standard for Urban Wastewater Treatment Plants" (GB18918-2002), which requires COD ≤ 50 mg / L, total nitrogen ≤ 15 mg / L, and total phosphorus ≤ 0.5 mg / L. Therefore, whether considering the wastewater treatment efficiency or the phosphorus content in the effluent, the patent application number is 202411483993.2, and the patent name is the patent for the highway service area wastewater treatment device and method based on the AOOA-MBBR process. The wastewater treatment effect is not ideal.

[0005] In addition, due to the small scale of wastewater in highway service areas, the conventional denitrification and phosphorus removal processes face the problems of insufficient carbon sources for the influent and complex operation (such as the need to accurately control the dissolved oxygen concentration in the aerobic tank, the nitrification liquid return ratio, the sludge return ratio, the sludge concentration, the sludge age and other operating parameters). At the same time, it is also necessary to cope with seasonal temperature changes, which requires a high level of technical skills from the operators. When the secondary biochemical treatment cannot reduce the total phosphorus to below 0.5 mg / L, deep chemical phosphorus removal is required to accurately control the amount of coagulant added, which not only increases the length of the process and infrastructure costs, but also increases the operating costs and difficulty of operation. How to remove the total nitrogen and total phosphorus from the wastewater in highway service areas efficiently, at low cost and with simple operation has become a difficult problem.

[0006] Therefore, there is an urgent need for a highway service area wastewater treatment technology that can improve wastewater treatment efficiency, remove total phosphorus, and has low cost and simple operation. Summary of the invention

[0007] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a highway service area wastewater treatment method based on anaerobic ammonia oxidation enhanced AOOA-MBBR, which can make the effluent total nitrogen and total phosphorus reach the corresponding emission standards (≤15mg / L, ≤0.5mg / L) when the hydraulic retention time is 20h, thereby improving the highway service area wastewater treatment efficiency and avoiding the subsequent troublesome phosphorus removal.

[0008] In order to solve the above technical problems, the technical solution of the present invention is: a highway service area wastewater treatment method based on anaerobic ammonium oxidation enhanced AOOA-MBBR, the method comprising:

[0009] The first step is to prepare the reactor:

[0010] The reactor comprises a first anoxic tank, a first aerobic tank, a second aerobic tank and a second anoxic tank which are connected in sequence, and fillers are added respectively. The first aerobic tank and the second aerobic tank are respectively provided with aeration devices; the second aerobic tank is connected with the first anoxic tank through a reflux pipe provided with a reflux power assembly;

[0011] The second step is to start the reactor and inoculate the bacteria:

[0012] The wastewater from the expressway service area flows through the first anoxic tank, the first aerobic tank, the second aerobic tank and the second anoxic tank in sequence; wherein, hydrolytic bacteria and denitrifying bacteria are inoculated in the first anoxic tank; hydrolytic bacteria, nitrifying bacteria and denitrifying bacteria are inoculated in the first aerobic tank; nitrifying bacteria are inoculated in the second aerobic tank, and hydrolytic bacteria and denitrifying bacteria are inoculated in the second anoxic tank; the dissolved oxygen concentration in the first aerobic tank is 0.3-0.5 mg / L; the dissolved oxygen concentration in the second aerobic tank is 2.0-2.5 mg / L; the hydraulic retention time is 48 hours; the nitrified liquid is returned from the second aerobic tank to the first anoxic tank, and the return ratio is 200%;

[0013] After the water output has been running stably for a preset time, the hydraulic retention time is gradually shortened to 36h, 24h, and 20h;

[0014] The third step is anaerobic ammonium oxidation enhancement:

[0015] After the effluent has been running stably for a preset time, fillers containing biofilm-forming anaerobic ammonia-oxidizing bacteria are used to replace some of the fillers in the first anoxic tank, the first aerobic tank, the second aerobic tank, and the second anoxic tank; the dissolved oxygen concentration in the first aerobic tank is 0.2 mg / L, and the dissolved oxygen concentration in the second aerobic tank is 0.5-0.8 mg / L; some wastewater from highway service areas is directly pumped into the second anoxic tank after adding manganese sulfate;

[0016] The fourth step is to enter the stabilization stage after the water output stabilizes.

[0017] Furthermore, in the third step, during the process of replacing the filler, the replacement is carried out in two steps, the first time replacing 4% of the filler in each pool, and the second time replacing 2% of the filler in each pool.

[0018] Furthermore, in the third step, the dosage of manganese was 3.5 mg / L, and the ratio of the highway service area wastewater directly pumped into the second anoxic tank to the highway service area wastewater pumped into the first anoxic tank was 1%.

[0019] Furthermore, the first anoxic tank, the first aerobic tank, the second aerobic tank and the second anoxic tank respectively use the volume of the added filler as the effective volume.

[0020] Further, during the second step of inoculation:

[0021] In the first anoxic tank, hydrolytic bacteria were inoculated once every 10 days, 200 mL each time, the bacterial solution concentration was 3-5 g / L, and a total of 8 inoculations; denitrifying bacteria were inoculated once every 5 days, 300 mL each time, the bacterial solution concentration was 8-10 g / L, and a total of 4 inoculations;

[0022] In the first aerobic pool, hydrolytic bacteria were inoculated once every 10 days, 150 mL each time, the bacterial solution concentration was 3-5 g / L, and the inoculation was performed 8 times; nitrifying bacteria and denitrifying bacteria were inoculated once every 5 days, 100 mL each time, the bacterial solution concentration was 8-10 g / L, and the inoculation was performed 4 times respectively;

[0023] In the second aerobic pool, nitrifying bacteria were inoculated once every 5 days, 400 mL each time, with a bacterial solution concentration of 8-10 g / L, and inoculated 4 times;

[0024] In the second anoxic tank, hydrolytic bacteria were inoculated once every 10 days, 100 mL each time, the bacterial solution concentration was 3-5 g / L, and the inoculation was 8 times; denitrifying bacteria were inoculated once every 5 days, 100 mL each time, the bacterial solution concentration was 8-10 g / L, and the inoculation was 4 times.

[0025] Furthermore, the carbon-nitrogen ratio COD / TN of highway service area wastewater is 1.67-1.70.

[0026] After adopting the above technical solution, the present invention has the following beneficial effects:

[0027] 1) The total nitrogen removal effect is very good: when treating wastewater from highway service areas with extremely low carbon-nitrogen ratio (COD / TN=1.67-1.70), the total nitrogen was reduced from about 150mg / L to 3.36mg / L when the hydraulic retention time was 20h, and the removal rate was 97.77%. The total nitrogen in the effluent was significantly lower than the Class A emission standard of the Pollutant Discharge Standard for Urban Wastewater Treatment Plants (GB18918-2002).

[0028] 2) Enhanced COD removal effect: By replacing the filler of biofilm anaerobic ammonium oxidizing bacteria, the COD removal effect was enhanced, and the effluent COD was significantly reduced from 14.58 mg / L before anaerobic ammonium oxidation enhancement to 9.05 mg / L, and the removal rate was increased from 94.26% before anaerobic ammonium oxidation enhancement to 96.44%. The effluent COD is significantly lower than the Class A emission standard of the Pollutant Discharge Standard for Urban Wastewater Treatment Plants (GB18918-2002).

[0029] 3) Simple operation and easy control: In view of the small scale of wastewater in highway service areas and the low technical level of operators, the first aerobic pool is set with a dissolved oxygen of about 0.2 mg / L, with the main goal of removing total nitrogen; the dissolved oxygen in aerobic pool 2 is 0.5-0.8 mg / L, with the main goal of completing ammonia nitrogen nitrification; the nitrate nitrogen in the effluent of the second aerobic pool can be removed in the second anoxic pool, because the operator can adjust the proportion of water pumped into the second anoxic pool according to the nitrate nitrogen concentration in the effluent of the second aerobic pool 2, providing sufficient electron donors for short-range denitrification anaerobic ammonia oxidation and denitrification denitrification. While achieving efficient removal of carbon, nitrogen and phosphorus, it is convenient for operators to control operating parameters.

[0030] 4) Total phosphorus is removed simultaneously: manganese pumped into the second anoxic tank is used to remove phosphorus through precipitation reaction, achieving simultaneous removal of carbon, nitrogen and phosphorus. The total phosphorus in the effluent is reduced to 0.27 mg / L, and the removal rate reaches 94.71%. The total phosphorus in the effluent is significantly lower than the Class A emission standard of the "Pollutant Discharge Standard for Urban Wastewater Treatment Plants" (GB18918-2002).

[0031] 5) Realizes efficient simultaneous removal of carbon, nitrogen and phosphorus: The present invention can simultaneously reduce carbon, nitrogen and phosphorus to below the Class A emission standard (COD≤50mg / L, total nitrogen≤15mg / L, total phosphorus≤0.5mg / L) of the Pollutant Discharge Standard for Urban Sewage Treatment Plants (GB18918-2002).

[0032] In summary, the present invention effectively solves the technical problem that the total nitrogen and total phosphorus in the effluent cannot meet the corresponding emission standards (≤15mg / L, ≤0.5mg / L) when the hydraulic retention time is 20h, and realizes the low-cost, high-efficiency and simple-operation removal of COD, total nitrogen and total phosphorus. After the wastewater from the highway service area is treated by the anaerobic ammonia oxidation enhanced A00A-MBBR process, it can meet the requirements of the first-level A emission standard of the "Pollutant Discharge Standard for Urban Sewage Treatment Plants" (GB18918-2002) for COD≤50mg / L, total nitrogen≤15mg / L, and total phosphorus≤0.5mg / L. It has high application value and is conducive to promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a flow chart of the highway service area wastewater treatment method based on anaerobic ammonium oxidation enhanced AOOA-MBBR of the present invention;

[0034] Figure 2 It is a structural schematic diagram of the reactor of the present invention;

[0035] Figure 3 This is a diagram showing the removal effect of COD during treatment in an embodiment of the present invention;

[0036] Figure 4 This is a diagram showing the effect of removing ammonia nitrogen during treatment in an embodiment of the present invention;

[0037] Figure 5 This is a diagram showing the effect of removing nitrate nitrogen during treatment in an embodiment of the present invention;

[0038] Figure 6 This is a diagram showing the effect of removing nitrite nitrogen during treatment in an embodiment of the present invention;

[0039] Figure 7 This is a diagram showing the effect of total nitrogen removal during treatment in an embodiment of the present invention;

[0040] Figure 8 This is a diagram showing the removal effect of total phosphorus during treatment in an embodiment of the present invention;

[0041] Fig. 9 It is a diagram of the amount of manganese added in the second anoxic tank 4 as the treatment is carried out in the embodiment of the present invention;

[0042] Fig.10The XRD diagram of the second anoxic pool 4 in the embodiment of the present invention is as follows;

[0043] Fig.11 This is a microbial detection diagram of the stable stage before adding anaerobic ammonia-oxidizing bacteria in an embodiment of the present invention;

[0044] Fig.12 This is a microbial detection diagram of the stable stage after adding anaerobic ammonia-oxidizing bacteria in an embodiment of the present invention;

[0045] In the figure, 1. the first anoxic tank; 2. the first aerobic tank; 3. the second aerobic tank; 4. the second anoxic tank; 5. the filler; 6. the reflux power assembly; 7. the peristaltic pump; 8. the aeration device. DETAILED DESCRIPTION

[0046] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments in conjunction with the accompanying drawings.

[0047] like Figure 1 and Figure 2 As shown, a highway service area wastewater treatment method based on anaerobic ammonium oxidation enhanced AOOA-MBBR, the method comprising:

[0048] The first step is to prepare the reactor:

[0049] The reactor comprises a first anoxic tank 1, a first aerobic tank 2, a second aerobic tank 3 and a second anoxic tank 4 which are connected in sequence, and a filler 5 is added respectively. The first aerobic tank 2 and the second aerobic tank 3 are respectively provided with an aeration device 8; the second aerobic tank 3 is connected to the first anoxic tank 1 through a reflux pipe 7 provided with a reflux power assembly 6;

[0050] Among them, the reactor has a length of 650mm, a width of 220mm and a height of 360mm. The effective volumes of the first anoxic tank 1, the first aerobic tank 2, the second aerobic tank 3 and the second anoxic tank 4 are 10.8L, 8.1L, 8.1L and 5.4L respectively. Filler 5 is added to each of the above-mentioned tanks, and the amount of filler 5 added is 10.8L, 8.1L, 8.1L and 5.4L respectively, that is, the effective volume is filled with filler 5 to ensure that the microorganisms are attached to the filler 5, which is conducive to the growth of microorganisms with a long generation cycle; filler 5 is K1MBBR fluidized bed filler with a diameter of 10mm, a density of about 1g / cm3, and a specific surface area of ​​60m 2 / m3, the filler 5 only provides a carrier for microbial growth and cannot be decomposed by microorganisms. The carbon-nitrogen ratio COD / TN of highway service area wastewater is 1.67-1.70, and the COD, ammonia nitrogen, total nitrogen and total phosphorus concentrations of simulated highway service area wastewater are about 250mg / L, 140mg / L, 150mg / L and 5mg / L respectively.

[0051] The second step is to start the reactor and inoculate the bacteria:

[0052] The wastewater from the highway service area flows through the first anoxic tank 1, the first aerobic tank 2, the second aerobic tank 3 and the second anoxic tank 4 in sequence; wherein, hydrolytic bacteria and denitrifying bacteria are inoculated in the first anoxic tank 1; hydrolytic bacteria, nitrifying bacteria and denitrifying bacteria are inoculated in the first aerobic tank 2; nitrifying bacteria are inoculated in the second aerobic tank 3, and hydrolytic bacteria and denitrifying bacteria are inoculated in the second anoxic tank 4; the dissolved oxygen concentration in the first aerobic tank 2 is 0.3-0.5 mg / L; the dissolved oxygen concentration in the second aerobic tank 3 is 2.0-2.5 mg / L; the hydraulic retention time is 48 hours; the nitrified liquid is returned from the second aerobic tank 3 to the first anoxic tank 1, and the return ratio is 200%; after the effluent is stabilized, the hydraulic retention time is shortened to 36 hours, after the effluent is stabilized for the second time, the hydraulic retention time is shortened to 24 hours, and after the effluent is stabilized for the third time, the hydraulic retention time is shortened to 20 hours.

[0053] In this step, during the inoculation process: in the first anoxic pool 1, hydrolytic bacteria are inoculated once every 10 days, 200 mL each time, the bacterial solution concentration is 3-5 g / L, and a total of 8 inoculations; denitrifying bacteria are inoculated once every 5 days, 300 mL each time, the bacterial solution concentration is 8-10 g / L, and a total of 4 inoculations; in the first aerobic pool 2, hydrolytic bacteria are inoculated once every 10 days, 150 mL each time, the bacterial solution concentration is 3-5 g / L, and a total of 8 inoculations; nitrifying bacteria and denitrifying bacteria are inoculated once every 5 days, respectively. 100mL was inoculated each time, the bacterial solution concentration was 8-10g / L, and it was inoculated 4 times respectively; in the second aerobic pool 3, nitrifying bacteria were inoculated once every 5 days, 400mL was inoculated each time, the bacterial solution concentration was 8-10g / L, and it was inoculated 4 times; in the second anoxic pool 4, hydrolytic bacteria were inoculated once every 10 days, 100mL was inoculated each time, the bacterial solution concentration was 3-5g / L, and it was inoculated 8 times; denitrifying bacteria were inoculated once every 5 days, 100mL was inoculated each time, the bacterial solution concentration was 8-10g / L, and it was inoculated 4 times.

[0054] The third step is anaerobic ammonium oxidation enhancement:

[0055] After the effluent is running stably for 13, fillers 5 containing biofilm-forming anaerobic ammonia-oxidizing bacteria are used to replace 6% of the fillers 5 in the first anoxic tank 1, the first aerobic tank 2, the second aerobic tank 3 and the second anoxic tank 4 twice (about 4% for the first replacement and about 2% for the second replacement), and the fillers 5 are the same as the above-mentioned K1MBBR fluidized bed fillers; the dissolved oxygen concentration in the first aerobic tank 2 is controlled at about 0.2 mg / L, and the dissolved oxygen concentration in the second aerobic tank 3 is controlled at 0.5-0.8 mg / L; manganese sulfate is added to part of the highway service area wastewater and then directly pumped into the second anoxic tank 4 through a peristaltic pump 7, the dosage of manganese is 3.5 mg / L, and the ratio of the highway service area wastewater directly pumped into the second anoxic tank 4 to the highway service area wastewater pumped into the first anoxic tank 1 is about 1%.

[0056] The fourth step is to wait for the effluent to stabilize and enter the stable stage. When the hydraulic retention time is 20h, COD, total nitrogen and total phosphorus are reduced from about 254mg / L, 150mg / L and 5mg / L to 8.17-9.95mg / L, 3.27-3.48mg / L and 0.25-0.31mg / , respectively, and the removal rates are 96.09%-96.79%, 97.69%-97.82% and 93.83%-95.18%; the average concentrations are 9.05mg / L, 3.36mg / L and 0.27mg / L, respectively, and the average removal rates are 96.43%, 97.77% and 94.71%. The effluent COD, total nitrogen and total phosphorus are significantly better than the Class A emission standard of "Pollutant Discharge Standard for Urban Wastewater Treatment Plants" (GB18918-2002).

[0057] Among them, in this embodiment, the return ratio refers to the ratio of the flow rate of the nitrification liquid returned from the second aerobic tank 3 to the first anoxic tank 1 to the flow rate of the highway service area wastewater entering the first anoxic tank 1 from the sewage inlet of the first anoxic tank 1. The effluent stability means that the COD, ammonia nitrogen, total nitrogen and total phosphorus concentrations in the water do not fluctuate by more than 10% relative to the average concentrations of COD, ammonia nitrogen, total nitrogen and total phosphorus in 13 consecutive days.

[0058] It should be noted that this embodiment is a further improvement on the patent with application number 202411483993.2 and patent name of highway service area wastewater treatment device and method based on AOOA-MBBR process. The hydraulic retention time is shortened to 24h from the first step to the second step, which is the same as the wastewater treatment method in the patent with application number 202411483993.2 and patent name of highway service area wastewater treatment device and method based on AOOA-MBBR process. Figure 3 To Attachment Fig. 9The 0th day in the above refers to the 0th day after the hydraulic retention time is shortened to 20h. The filler 5 of the biofilm anaerobic ammonia oxidizing bacteria is replaced for the first time on the 37th day, and the filler 5 of the biofilm anaerobic ammonia oxidizing bacteria is replaced for the second time on the 41st day. The anaerobic ammonia oxidizing bacteria filler in the first anoxic tank 1 is placed opposite to the outlet of the reflux nitrification liquid to reduce the influence of the dissolved oxygen carried in the reflux nitrification liquid on the anaerobic ammonia oxidizing bacteria, and is concentrated in 3 places to form an aggregation effect, which is conducive to the function of anaerobic ammonia oxidizing bacteria. The anaerobic ammonia oxidizing bacteria filler in the first aerobic tank 2 and the second aerobic tank 3 is placed near the 4 corners (the aeration device 8 is located in the center), and the anaerobic ammonia oxidizing bacteria filler is far away from the aeration device 8 to reduce the influence of dissolved oxygen on the anaerobic ammonia oxidizing bacteria and form an aggregation effect, which is conducive to the function of anaerobic ammonia oxidizing bacteria. The anaerobic ammonia oxidizing bacteria filler in the second anoxic pool 4 is placed opposite to the connection between the second aerobic pool 3 and the second anoxic pool 4, reducing the impact of dissolved oxygen carried in the effluent of the second aerobic pool 3 on the anaerobic ammonia oxidizing bacteria, and concentrated in 3 places to form an aggregation effect, which is conducive to the function of anaerobic ammonia oxidizing bacteria. The fourth step of the stable stage refers to the 69th to 81st day. Manganese (manganese sulfate) was added from the 57th day, and the dosage was gradually increased to 3.5 mg / L according to the effluent phosphorus concentration.

[0059] Among them, in the filler 5 of biofilm-forming anaerobic ammonia-oxidizing bacteria, the anaerobic ammonia-oxidizing bacteria grow on the solid filler 5, which can be but is not limited to 0.2g-0.3g / g.

[0060] The sewage treatment method involved in the above embodiment is introduced in detail from the principle aspect below.

[0061] In view of the extremely low carbon-nitrogen ratio (COD / TN=1.67-1.70) of wastewater from highway service areas, a highway service area wastewater treatment method based on anaerobic ammonia oxidation enhanced AOOA-MBBR was developed. Hydrolytic bacteria, denitrifying bacteria, and anaerobic ammonia oxidizing bacteria are inoculated on the filler 5 of the first anoxic tank 1. The influent and the nitrification liquid from the second aerobic tank 3 are mixed on the upper part of the filler 5 of the first anoxic tank 1 and then flow through the filler 5. The denitrifying bacteria attached to the filler 5 first use the easily degradable organic matter in the influent as a carbon source to reduce the nitrate nitrogen carried in the reflux nitrification liquid to nitrite nitrogen; the anaerobic ammonia oxidizing bacteria use the ammonia nitrogen in the influent as an electron acceptor to reduce the nitrite nitrogen to nitrogen gas, and the remaining nitrite nitrogen is further denitrified to nitrogen gas by the denitrifying bacteria using the organic matter in the influent or the hydrolysis products of the difficult-to-degrade organic matter as a carbon source. Under the condition of severe shortage of carbon source, after long-term cultivation and domestication, efficient hydrolytic bacteria will be produced on the filler 5; the efficient hydrolytic bacteria attached to the filler 5 can hydrolyze the difficult-to-degrade organic matter in the influent into easily degradable organic matter, thereby providing a carbon source for denitrification. The biofilm detached from the filler 5 can also be hydrolyzed by the efficient hydrolytic bacteria into easily degradable organic matter, providing a carbon source for denitrification. In addition, after replacing the filler 5 with anaerobic ammonia-oxidizing bacteria attached, the COD removal effect was enhanced; the COD concentration in the first anoxic tank 1 dropped significantly from an average of 19.25 mg / L (range 17.50 mg / L-20.82 mg / L) to an average of 13.58 mg / L (range 12.40 mg / L-14.62 mg / L), which can prove the above point of view. The reason is that the filler 5 to which the anaerobic ammonium oxidizing bacteria are attached is not only attached with the anaerobic ammonium oxidizing bacteria, but also attached with a certain amount of hydrolytic bacteria and denitrifying bacteria. Since the generation cycle of anaerobic ammonium oxidizing bacteria is very long, sludge is usually not discharged during the anaerobic ammonium oxidizing bacteria biofilm formation process, and the dead microorganisms will be hydrolyzed and then used as a carbon source for denitrification. Therefore, the filler 5 is attached with anaerobic ammonium oxidizing bacteria, high-efficiency hydrolytic bacteria, and denitrifying bacteria, which can further degrade the difficult-to-degrade organic matter in the first anoxic tank 1.

[0062] In the first aerobic tank 2, by controlling the dissolved oxygen at about 0.2 mg / L, an aerobic layer composed mainly of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) is formed on the outer layer of the biofilm on the filler 5, and an anoxic layer composed mainly of anaerobic ammonia oxidizing bacteria, high-efficiency hydrolytic bacteria and denitrifying bacteria is formed on the inner layer of the biofilm on the filler 5, thereby achieving denitrification by anaerobic ammonia oxidation, short-range denitrification anaerobic ammonia oxidation, short-range nitrification and denitrification, and simultaneous nitrification and denitrification. The AOB on the outer layer of the filler 5 of the first aerobic tank 2 oxidizes the ammonia nitrogen in the effluent of the first anoxic tank 1 to nitrite nitrogen, and the anaerobic ammonia oxidizing bacteria uses the nitrite nitrogen produced by the oxidation of ammonia nitrogen as an electron acceptor to oxidize the ammonia nitrogen in the effluent of the first anoxic tank 1 to nitrogen gas, thereby achieving anaerobic ammonia oxidation denitrification; the denitrifying bacteria use the hydrolysis products of the difficult-to-degrade organic matter or the hydrolysis products of the detached biofilm as a carbon source to reduce the nitrite nitrogen to nitrogen gas, thereby achieving short-range nitrification and denitrification; at the same time, NOB converts part of the nitrite nitrogen into nitrogen gas. Nitrogen is further oxidized to nitrate nitrogen, and denitrifying bacteria use the hydrolysis products of refractory organic matter or the hydrolysis products of detached biofilm as carbon sources to reduce nitrate nitrogen to nitrite nitrogen. Anaerobic ammonia oxidizing bacteria use the nitrite nitrogen produced by nitrate nitrogen denitrification as an electron acceptor to oxidize ammonia nitrogen in the effluent of the first anoxic pool 1 to nitrogen gas, realizing short-term denitrification and anaerobic ammonia oxidation denitrification; nitrite nitrogen produced by nitrate nitrogen denitrification will also be further denitrified to nitrogen gas by denitrifying bacteria, realizing simultaneous nitrification and denitrification. In the first aerobic pool 2, the total nitrogen dropped significantly from an average of 22.19 mg / L (range 21.71 mg / L-22.44 mg / L) to an average of 15.67 mg / L (range 15.29 mg / L-16.12 mg / L), proving that total nitrogen is removed by anaerobic ammonia oxidation, short-term denitrification and anaerobic ammonia oxidation, short-term nitrification and denitrification, and simultaneous nitrification and denitrification. In addition, COD only dropped from an average of 13.58 mg / L (range 12.40 mg / L-14.62 mg / L) to an average of 11.66 mg / L (range 10.51 mg / L-12.73 mg / L), further proving the total nitrogen removal method; because the removal of total nitrogen by anaerobic ammonia oxidation does not require a carbon source, the removal of 1 mg of total nitrogen (ammonia nitrogen + nitrate nitrogen) by short-range denitrification anaerobic ammonia oxidation theoretically only requires the consumption of 0.74 mg COD, and the removal of 1 mg of total nitrogen by short-range nitrification and denitrification theoretically only requires the consumption of 1.72 mg COD.

[0063] The dissolved oxygen in the second aerobic pool 3 is controlled at 0.5-0.8 mg / L, and an aerobic layer mainly composed of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) is formed on the outer layer of the biofilm on the filler 5, and an anoxic layer mainly composed of anaerobic ammonia oxidizing bacteria, high-efficiency hydrolytic bacteria and denitrifying bacteria is formed on the inner layer of the biofilm on the filler 5, so as to achieve denitrification by anaerobic ammonia oxidation, short-range denitrification anaerobic ammonia oxidation, short-range nitrification and denitrification, and simultaneous nitrification and denitrification. The first aerobic pool 2 and the second aerobic pool 3 are set for different purposes. The first aerobic pool 2 is mainly aimed at removing total nitrogen, and at the same time, part of the ammonia nitrogen is oxidized to nitrate nitrogen, so the dissolved oxygen in the first aerobic pool 2 is controlled at about 0.2 mg / L. The second aerobic pool 3 is mainly aimed at completing the nitrification of ammonia nitrogen, achieving the purpose of convenient operation, and at the same time removing part of the total nitrogen, so the dissolved oxygen in the second aerobic pool 3 is controlled at 0.5-0.8 mg / L. The concentrations of dissolved oxygen in the first aerobic tank 2 and the second aerobic tank 3 are different, resulting in different thicknesses of the aerobic layer and the anoxic layer of the biofilm, that is, the ratios of aerobic AOB, NOB and anoxic anaerobic ammonia oxidizing bacteria, denitrifying bacteria, and high-efficiency hydrolytic bacteria in the biofilm are different. The AOB on the outer layer of the filler 5 of the second aerobic tank 3 oxidizes the ammonia nitrogen in the effluent of the first aerobic tank 2 to nitrite nitrogen. The anaerobic ammonia oxidizing bacteria uses the nitrite nitrogen produced by the oxidation of ammonia nitrogen as an electron acceptor to oxidize the ammonia nitrogen in the effluent of the first aerobic tank 2 to nitrogen gas, thereby achieving anaerobic ammonia oxidation denitrification. The denitrifying bacteria use the hydrolysis products of difficult-to-degrade organic matter or the hydrolysis products of the detached biofilm as a carbon source to reduce the nitrite nitrogen to nitrogen gas, thereby achieving short-term nitrification and denitrification. At the same time, NOB converts part of the nitrite nitrogen into nitrogen gas. Nitrogen is further oxidized to nitrate nitrogen, and denitrifying bacteria use the hydrolysis products of refractory organic matter or the hydrolysis products of detached biofilm as carbon sources to reduce nitrate nitrogen to nitrite nitrogen. Anaerobic ammonia-oxidizing bacteria use the nitrite nitrogen produced by nitrate nitrogen denitrification as an electron acceptor to oxidize ammonia nitrogen in the effluent of the first aerobic pool 2 to nitrogen gas, achieving short-range denitrification and anaerobic ammonia oxidation denitrification; nitrite nitrogen produced by nitrate nitrogen denitrification will also be further denitrified to nitrogen gas by denitrifying bacteria, achieving simultaneous nitrification and denitrification. In addition, due to the high dissolved oxygen concentration in the second aerobic pool 3, the ammonia nitrogen in the effluent of the second aerobic pool 3 dropped to an average of 0.73 mg / L (range 0.65 mg / L-0.80 mg / L), achieving the goal of ammonia nitrogen nitrification. In the second aerobic pool 3, the total nitrogen dropped significantly from an average of 15.67 mg / L (range 15.29 mg / L-16.12 mg / L) to an average of 10.90 mg / L (range 10.31 mg / L-11.45 mg / L), proving that the total nitrogen was removed by anaerobic ammonium oxidation, short-cut denitrification anaerobic ammonium oxidation, short-cut nitrification and denitrification, and simultaneous nitrification and denitrification. In addition, COD only dropped from an average of 11.66 mg / L (range 10.51 mg / L-12.73 mg / L) to an average of 10.25 mg / L (range 9.49 mg / L-10.95 mg / L), further proving the removal method of total nitrogen.

[0064] In the second anoxic tank 4, since the total nitrogen in the effluent from the second aerobic tank 3 is mainly nitrate nitrogen (nitrate nitrogen is about 8 mg / L (range is 8.12 mg / L-8.28 mg / L), nitrite nitrogen is about 0.9 mg / L (range is 0.81 mg / L-1.01 mg / L), ammonia nitrogen is about 0.7 mg / L (range is 0.65 mg / L-0.80 mg / L), and organic nitrogen is about 1 mg / L (range is 0.46 mg / L-1.69 mg / L)), and the COD in the effluent from the second aerobic tank 3 is only 10.25 mg / L (range is 9.49 mg / L-10.95 mg / L); the carbon source in the effluent from the second aerobic tank 3 is limited and cannot meet the carbon source demand of denitrification and denitrification. In addition, the total phosphorus in the effluent of the second aerobic pool 3 is 1.89mg / L-1.99mg / L, which cannot meet the discharge requirement of total phosphorus ≤ 0.5mg / L. In view of this, the influent with about 1% manganese sulfate is directly pumped into the second anoxic pool 4, so that the dosage of manganese is about 3.5mg / L; at the same time, the filler 5 of biofilm anaerobic ammonia oxidizing bacteria is replaced, and phosphorus is removed in the second anoxic pool 4 through short-range denitrification anaerobic ammonia oxidation, denitrification and denitrification, and phosphate precipitation reaction with manganese. Highly efficient hydrolytic bacteria, denitrifying bacteria, and anaerobic ammonia oxidizing bacteria will be cultivated and domesticated on the filler 5 of the second anoxic pool 4. Denitrifying bacteria use the easily degradable organic matter in the influent as a carbon source to reduce the nitrate nitrogen in the effluent of the second aerobic tank 3 to nitrite nitrogen. Anaerobic ammonia-oxidizing bacteria use the ammonia nitrogen in the influent as an electron donor to reduce the nitrite nitrogen produced by denitrification of nitrate nitrogen to nitrogen gas. At the same time, part of the nitrite nitrogen is further denitrified to nitrogen gas by denitrifying bacteria using the organic matter in the influent or the hydrolysis products of the difficult-to-degrade organic matter as a carbon source. High-efficiency hydrolytic bacteria are also trained in the second anoxic tank 4, which can hydrolyze the difficult-to-degrade organic matter in the influent into easily degradable organic matter, providing a carbon source for denitrification. The biofilm that falls off the filler 5 can also be hydrolyzed by the high-efficiency hydrolytic bacteria into easily degradable organic matter, providing a carbon source for denitrification. The manganese in the influent directly pumped into the second anoxic tank 4 can react with phosphate to produce a precipitate of manganese phosphate; the manganese phosphate produced in the second anoxic tank 4 can be adsorbed onto the filler 5 by the biofilm to achieve phosphorus removal ( Fig.10 This indicates that manganese and phosphorus reacted to produce a precipitation reaction, and the resulting manganese phosphate precipitate adhered to the filler. The precipitate did not flow away with the effluent and would not cause secondary pollution).

[0065] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A highway service area wastewater treatment method based on anaerobic ammonium oxidation enhanced AOOA-MBBR, characterized in that: Methods include: The first step is to prepare the reactor: The reactor comprises a first anoxic tank (1), a first aerobic tank (2), a second aerobic tank (3) and a second anoxic tank (4) which are connected in sequence, and fillers (5) are added respectively. The first aerobic tank (2) and the second aerobic tank (3) are respectively provided with an aeration device (8); the second aerobic tank (3) is connected to the first anoxic tank (1) via a reflux pipe (7) provided with a reflux power assembly (6); The second step is to start the reactor and inoculate the bacteria: Wastewater from a highway service area flows through a first anoxic tank (1), a first aerobic tank (2), a second aerobic tank (3) and a second anoxic tank (4) in sequence; wherein hydrolytic bacteria and denitrifying bacteria are inoculated in the first anoxic tank (1); hydrolytic bacteria, nitrifying bacteria and denitrifying bacteria are inoculated in the first aerobic tank (2); nitrifying bacteria are inoculated in the second aerobic tank (3), and hydrolytic bacteria and denitrifying bacteria are inoculated in the second anoxic tank (4); the dissolved oxygen concentration in the first aerobic tank (2) is 0.3-0.5 mg / L; the dissolved oxygen concentration in the second aerobic tank (3) is 2.0-2.5 mg / L; the hydraulic retention time is 48 hours; the nitrified liquid is returned from the second aerobic tank (30.5-0.8) to the first anoxic tank (1), and the return ratio is 200%; After the water output has been running stably for a preset time, the hydraulic retention time is gradually shortened to 36h, 24h, and 20h; The third step is anaerobic ammonium oxidation enhancement: After the effluent has been running stably for a preset time, fillers (5) containing biofilm-forming anaerobic ammonia-oxidizing bacteria are used to replace part of the fillers (5) in the first anoxic tank (1), the first aerobic tank (2), the second aerobic tank (3) and the second anoxic tank (4); the dissolved oxygen concentration in the first aerobic tank (2) is 0.2 mg / L, and the dissolved oxygen concentration in the second aerobic tank (3) is 0.5-0.8 mg / L; and manganese sulfate is added to part of the wastewater from the highway service area and then directly pumped into the second anoxic tank (4); The fourth step is to enter the stabilization stage after the water output stabilizes.

2. The highway service area wastewater treatment method based on anaerobic ammonium oxidation enhanced AOOA-MBBR according to claim 1 is characterized in that: In the third step, during the process of replacing the filler (5), the replacement is carried out in two steps. The first time, 4% of the filler (5) in each pool is replaced, and the second time, 2% of the filler (5) in each pool is replaced.

3. The highway service area wastewater treatment method based on anaerobic ammonium oxidation enhanced AOOA-MBBR according to claim 1 is characterized in that: In the third step, the dosage of manganese is 3.5 mg / L, and the ratio of the highway service area wastewater directly pumped into the second anoxic tank (4) to the highway service area wastewater pumped into the first anoxic tank (1) is 1%.

4. The highway service area wastewater treatment method based on anaerobic ammonium oxidation enhanced AOOA-MBBR according to claim 1 is characterized in that: The first anoxic tank (1), the first aerobic tank (2), the second aerobic tank (3) and the second anoxic tank (4) respectively use the volume of the added filler (5) as the effective volume.

5. The method for treating highway service area wastewater based on anaerobic ammonium oxidation enhanced AOOA-MBBR according to claim 1, characterized in that: During the second step of inoculation: In the first anoxic tank (1), hydrolytic bacteria are inoculated once every 10 days, 200 mL each time, the bacterial solution concentration is 3-5 g / L, and a total of 8 inoculations are made; denitrifying bacteria are inoculated once every 5 days, 300 mL each time, the bacterial solution concentration is 8-10 g / L, and a total of 4 inoculations are made; In the first aerobic pool (2), hydrolytic bacteria are inoculated once every 10 days, 150 mL each time, the bacterial solution concentration is 3-5 g / L, and the inoculation is performed 8 times; nitrifying bacteria and denitrifying bacteria are inoculated once every 5 days, 100 mL each time, the bacterial solution concentration is 8-10 g / L, and the inoculation is performed 4 times; In the second aerobic pool (3), nitrifying bacteria are inoculated once every 5 days, 400 mL each time, and the concentration of the bacterial solution is 8-10 g / L, and the inoculation is performed 4 times; In the second anoxic tank (4), hydrolytic bacteria are inoculated once every 10 days, 100 mL each time, the bacterial solution concentration is 3-5 g / L, and the inoculation is performed 8 times; denitrifying bacteria are inoculated once every 5 days, 100 mL each time, the bacterial solution concentration is 8-10 g / L, and the inoculation is performed 4 times.

6. The highway service area wastewater treatment method based on anaerobic ammonium oxidation enhanced AOOA-MBBR according to claim 1 is characterized in that: The carbon-nitrogen ratio (COD / TN) of wastewater from highway service areas is 1.67-1.70.

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