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

Abstract

The present application relates to the field of expressway service area wastewater treatment, and particularly relates to a kind of expressway service area wastewater treatment method based on anaerobic ammonia oxidation enhanced AOOA-MBBR.Method includes: first, preparation reactor;Second, start reactor and inoculate bacteria, in this step, after the preset time of effluent stable operation, hydraulic retention time is gradually shortened to 20h;Third, anaerobic ammonia oxidation enhancement: after the preset time of effluent stable operation, using the packing of biofilm anaerobic ammonia oxidation bacteria replaces part of the packing in each pool;The dissolved oxygen concentration in the first aerobic tank is 0.2mg / L, the dissolved oxygen concentration in the second aerobic tank is 0.5-0.8mg / L;Part of the expressway service area wastewater is directly pumped into the second anoxic tank after adding manganese sulfate;Fourth, after the effluent is stable, enter the stable stage.The present application can make the total nitrogen and total phosphorus of effluent reach the corresponding discharge standard when the hydraulic retention time is 20h, thereby improving the expressway service area wastewater treatment efficiency, and avoiding the subsequent phosphorus removal problem.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high-speed service area wastewater treatment, in particular to a highway service area wastewater treatment method based on anaerobic ammonia oxidation enhanced AOOA-MBBR. BACKGROUND

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

[0003] In view of the high ammonia nitrogen concentration and low carbon-nitrogen ratio of the highway service area wastewater, the present inventors previously applied for a patent with the application number 202411483993.2 and the patent name of Highway Service Area Wastewater Treatment Device and Method Based on AOOA-MBBR Process. The patent achieves denitrification by culturing, domesticating, and enriching hydrolytic bacteria and denitrifying bacteria on the fillers of the first anoxic tank, achieves simultaneous nitrification and denitrification by culturing, domesticating, and enriching hydrolytic bacteria, nitrifying bacteria, and denitrifying bacteria on the fillers of the first aerobic tank, achieves nitrification of ammonia nitrogen in the effluent of the first aerobic tank by culturing, domesticating, and enriching nitrifying bacteria on the fillers of the second aerobic tank, and achieves denitrification by culturing, domesticating, and enriching hydrolytic bacteria and denitrifying bacteria on the fillers of the second anoxic tank. When the hydraulic retention time is 24 h, the average concentration of total nitrogen in the effluent after treatment is 14.33 mg / L, and the average removal rate is 90.49%. However, when the hydraulic retention time is reduced to 20 h, the total nitrogen in the effluent is difficult to reduce to below 15 mg / L, so the hydraulic retention time cannot be further reduced, resulting in low wastewater treatment efficiency. Moreover, in this patent, phosphorus is hardly removed.

[0004] Highway service area wastewater generally refers to the implementation of the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB18918-2002) Level A discharge standard, which requires COD ≤ 50 mg / L, total nitrogen ≤ 15 mg / L, and total phosphorus ≤ 0.5 mg / L. Therefore, in terms of wastewater treatment efficiency and phosphorus content in the effluent, the patent with the application number 202411483993.2 and the patent name of Highway Service Area Wastewater Treatment Device and Method Based on AOOA-MBBR Process is not ideal in terms of wastewater treatment effect.

[0005] In addition, due to the small scale of the highway service area wastewater, the conventional denitrification and phosphorus removal process faces the problems of insufficient carbon source in the influent, complex operation (such as the need for precise control of the dissolved oxygen concentration in the aerobic tank, the nitration liquid reflux ratio, the sludge reflux ratio, the sludge concentration, the sludge age, and other operating parameters), and the need to cope with seasonal temperature changes, which requires a high technical level of the operating personnel. When the total phosphorus cannot be reduced to below 0.5 mg / L by the secondary biochemical treatment, deep chemical phosphorus removal is needed, and the dosage of the coagulant needs to be accurately controlled, which not only increases the length of the process flow, the capital construction cost, but also increases the operation cost and the operation difficulty. How to efficiently, low-cost and simply remove the total nitrogen and total phosphorus in the highway service area wastewater has become a difficult point.

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

[0007] The technical problem to be solved by the present application 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 total nitrogen and total phosphorus in the effluent reach the corresponding discharge standard (≤15 mg / L, ≤0.5 mg / L) when the hydraulic retention time is 20 h, thereby improving the wastewater treatment efficiency of the highway service area and avoiding the subsequent phosphorus removal problem.

[0008] To solve the above technical problems, the technical scheme of the present application is: a highway service area wastewater treatment method based on anaerobic ammonia oxidation enhanced AOOA-MBBR, the method comprising:

[0009] First, prepare the reactor:

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

[0011] Second, start the reactor and inoculate bacteria:

[0012] The expressway service area wastewater flows through the first anoxic tank, the first aerobic tank, the second aerobic tank and the second anoxic tank in turn; wherein, the hydrolytic bacteria and denitrifying bacteria are inoculated in the first anoxic tank; the hydrolytic bacteria, nitrifying bacteria and denitrifying bacteria are inoculated in the first aerobic tank; the nitrifying bacteria are inoculated in the second aerobic tank, and the 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 h; the nitrification liquid is refluxed from the second aerobic tank to the first anoxic tank, and the reflux ratio is 200%;

[0013] After the effluent is stably operated for a preset time, the hydraulic retention time is gradually shortened to 36 h, 24 h and 20 h;

[0014] Third step, anaerobic ammonia oxidation strengthening:

[0015] After the effluent is stably operated for a preset time, the fillers with the biofilm of anaerobic ammonia oxidation bacteria are used to replace part 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; part of the expressway service area wastewater is directly pumped into the second anoxic tank after adding manganese sulfate;

[0016] Fourth step, after the effluent is stable, enter the stable stage.

[0017] Further, in the third step, the fillers are replaced twice, 4% of the fillers in each tank are replaced in the first replacement, and 2% of the fillers in each tank are replaced in the second replacement.

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

[0019] Further, the first anoxic tank, the first aerobic tank, the second aerobic tank and the second anoxic tank respectively take the volume of the added fillers as the effective volume.

[0020] Further, in the process of inoculating bacteria in the second step:

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

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

[0023] In the second aerobic tank, the nitrifying bacteria are inoculated once every 5 days, 400 mL each time, the concentration of the bacterial solution is 8-10 g / L, and the inoculation is performed 4 times;

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

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

[0026] After the above technical scheme is adopted, the present application has the following beneficial effects:

[0027] 1) The total nitrogen removal effect is very good: when treating the expressway service area wastewater with very low carbon-nitrogen ratio (COD / TN=1.67-1.70) and the hydraulic retention time is 20 h, the total nitrogen is reduced from about 150 mg / L to 3.36 mg / L, and the removal rate is 97.77%. The total nitrogen of the effluent is much lower than the first level A discharge standard of the "Urban Sewage Treatment Plant Pollutant Discharge Standard" (GB18918-2002).

[0028] 2) The COD removal effect is strengthened: by replacing the packing of the biofilm anammox bacteria, the COD removal effect is strengthened, the COD of the effluent is obviously reduced from 14.58 mg / L before the anammox strengthening to 9.05 mg / L, and the removal rate is increased from 94.26% before the anammox strengthening to 96.44%. The COD of the effluent is much lower than the first level A discharge standard of the "Urban Sewage Treatment Plant Pollutant Discharge Standard" (GB18918-2002).

[0029] 3) The operation is simple and easy to control: in view of the characteristics of small scale and low technical level of the operation personnel of the expressway service area wastewater; the dissolved oxygen of the first aerobic tank is about 0.2 mg / L, and the main target is to remove the total nitrogen; the dissolved oxygen of the second aerobic tank is 0.5-0.8 mg / L, and the main target is to complete the nitrification of ammonia nitrogen; the nitrate nitrogen in the effluent of the second aerobic tank can be removed in the second anoxic tank, because the operation personnel can adjust the proportion of the influent pumped into the second anoxic tank according to the concentration of the nitrate nitrogen in the effluent of the second aerobic tank, so as to provide sufficient electron donor for the short-cut denitrifying anammox and denitrification. While realizing the efficient removal of carbon, nitrogen and phosphorus, the operation personnel can easily control the operation parameters.

[0030] 4) Total phosphorus is removed synchronously: phosphorus is removed by precipitation reaction through manganese added into the second anoxic tank by pumping, realizing synchronous 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 obviously lower than the first level A emission standard in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB18918-2002).

[0031] 5) Carbon, nitrogen and phosphorus are simultaneously and efficiently removed: the present application can reduce carbon, nitrogen and phosphorus to below the first level A emission standard (COD≤50 mg / L, total nitrogen≤15 mg / L, total phosphorus≤0.5 mg / L) in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB18918-2002).

[0032] In summary, the present application effectively solves the technical problem that the total nitrogen and total phosphorus in the effluent cannot reach the corresponding emission standard (≤15 mg / L, ≤0.5 mg / L) when the hydraulic retention time is 20 h, and realizes low-cost, efficient and simple operation removal of COD, total nitrogen and total phosphorus. After the highway service area wastewater is treated by the anaerobic ammonia oxidation enhanced A00A-MBBR process, the COD, total nitrogen and total phosphorus in the effluent can reach the requirements of COD≤50 mg / L, total nitrogen≤15 mg / L and total phosphorus≤0.5 mg / L in the first level A emission standard in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB18918-2002). The present application has high application value and is conducive to popularization and application. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 It is a flow chart of the highway service area wastewater treatment method based on the anaerobic ammonia oxidation enhanced A00A-MBBR of the present application;

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

[0035] Figure 3 It is a COD removal effect diagram in the present application with the progress of treatment;

[0036] Figure 4 It is an ammonia nitrogen removal effect diagram in the present application with the progress of treatment;

[0037] Figure 5 It is a nitrate nitrogen removal effect diagram in the present application with the progress of treatment;

[0038] Figure 6 It is a nitrite nitrogen removal effect diagram in the present application with the progress of treatment;

[0039] Figure 7 It is a total nitrogen removal effect diagram in the present application with the progress of treatment;

[0040] Figure 8 Figure for removal effect of total phosphorus along with the progress of treatment in the embodiment of the present application;

[0041] Figure 9 Figure for manganese dosage amount in the second anoxic tank 4 along with the progress of treatment in the embodiment of the present application;

[0042] Figure 10 Figure for XRD in the second anoxic tank 4 along with the progress of treatment in the embodiment of the present application;

[0043] Figure 11 Figure for microbial detection in the stable stage before adding anammox bacteria in the embodiment of the present application;

[0044] Figure 12 Figure for microbial detection in the stable stage after adding anammox bacteria in the embodiment of the present application;

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

[0046] In order to make the content of the present application more easily understood, the present application will be further described in detail below according to specific embodiments and in conjunction with the accompanying drawings.

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

[0048] Step 1, preparation of 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 connected in sequence, filler 5 is added respectively, the first aerobic tank 2 and the second aerobic tank 3 are respectively provided with aeration devices 8; the second aerobic tank 3 is connected with the first anoxic tank 1 through a reflux pipe provided with a reflux power assembly 6;

[0050] The reactor has a length of 650 mm, a width of 220 mm and a height of 360 mm. 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 10.8 L, 8.1 L, 8.1 L and 5.4 L respectively. The filler 5 is added to each of the above tanks, and the amount of filler 5 added is 10.8 L, 8.1 L, 8.1 L and 5.4 L respectively, i.e. the effective volume is filled with the filler 5, so as to ensure that the microorganisms are attached to the filler 5, which is beneficial to the growth of microorganisms with long generation cycles; the filler 5 is K1MBBR fluidized bed filler, with a diameter of 10 mm, a density of about 1 g / cm3 and a specific surface area of 60 m2 / g. The filler 5 only provides a carrier for the growth of microorganisms and cannot be decomposed by microorganisms. The carbon-nitrogen ratio COD / TN of the expressway service area wastewater is 1.67-1.70, and the concentrations of COD, ammonia nitrogen, total nitrogen and total phosphorus in the simulated expressway service area wastewater are about 250 mg / L, 140 mg / L, 150 mg / L and 5 mg / L respectively. 2

[0051] In the second step, the reactor is started and inoculated with bacteria.

[0052] The expressway service area wastewater 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; the hydrolytic bacteria and denitrifying bacteria are inoculated in the first anoxic tank 1; the hydrolytic bacteria, nitrifying bacteria and denitrifying bacteria are inoculated in the first aerobic tank 2; the nitrifying bacteria are inoculated in the second aerobic tank 3, and the hydrolytic bacteria and denitrifying bacteria are inoculated in the second anoxic tank 4; the concentration of dissolved oxygen in the first aerobic tank 2 is 0.3-0.5 mg / L; the concentration of dissolved oxygen in the second aerobic tank 3 is 2.0-2.5 mg / L; the hydraulic retention time is 48 h; the nitrified liquid is backflowed from the second aerobic tank 3 to the first anoxic tank 1, and the backflow ratio is 200%; after the effluent is stable, the hydraulic retention time is shortened to 36 h, and after the effluent is stable for the second time, the hydraulic retention time is shortened to 24 h, and after the effluent is stable for the third time, the hydraulic retention time is shortened to 20 h.

[0053] ​In this step, the process of inoculating bacteria: in the first anoxic tank 1, hydrolytic bacteria were inoculated once every 10 days, 200 mL each time, with a concentration of 3-5 g / L, for a total of 8 times; denitrifying bacteria were inoculated once every 5 days, 300 mL each time, with a concentration of 8-10 g / L, for a total of 4 times; in the first aerobic tank 2, hydrolytic bacteria were inoculated once every 10 days, 150 mL each time, with a concentration of 3-5 g / L, for a total of 8 times; nitrifying bacteria and denitrifying bacteria were inoculated once every 5 days, 100 mL each time, with a concentration of 8-10 g / L, respectively, for a total of 4 times; in the second aerobic tank 3, nitrifying bacteria were inoculated once every 5 days, 400 mL each time, with a concentration of 8-10 g / L, for a total of 4 times; in the second anoxic tank 4, hydrolytic bacteria were inoculated once every 10 days, 100 mL each time, with a concentration of 3-5 g / L, for a total of 8 times; denitrifying bacteria were inoculated once every 5 days, 100 mL each time, with a concentration of 8-10 g / L, for a total of 4 times.

[0054] Third step, anaerobic ammonia oxidation enhancement:

[0055] After stable operation of the effluent for 13, the biofilm of the anaerobic ammonia oxidation bacteria was replaced twice, with 6% of the filler 5 in the first anoxic tank 1, the first aerobic tank 2, the second aerobic tank 3, and the second anoxic tank 4 being replaced (about 4% in the first replacement and about 2% in the second replacement), which was the same as the K1MBBR fluidized bed filler described above; the dissolved oxygen concentration in the first aerobic tank 2 was controlled at about 0.2 mg / L, and the dissolved oxygen concentration in the second aerobic tank 3 was controlled at 0.5-0.8 mg / L; part of the highway service area wastewater was pumped into the second anoxic tank 4 by the peristaltic pump 7 after adding manganese sulfate, with a manganese dosage of 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 was about 1%.

[0056] Fourth step, after the effluent is stable, enter the stable stage, when the hydraulic retention time is 20 h, the COD, total nitrogen, and total phosphorus are reduced from about 254 mg / L, 150 mg / L, and 5 mg / L to 8.17-9.95 mg / L, 3.27-3.48 mg / L, and 0.25-0.31 mg / L, respectively, with removal rates of 96.09%-96.79%, 97.69%-97.82%, and 93.83%-95.18%, respectively; the average concentrations are 9.05 mg / L, 3.36 mg / L, and 0.27 mg / L, respectively, and the average removal rates are 96.43%, 97.77%, and 94.71%, respectively. The effluent COD, total nitrogen, and total phosphorus are significantly better than the first level A emission standard of the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB 18918-2002).

[0057] Wherein, in the present embodiment, the reflux ratio refers to the ratio of the flow rate of the nitrification liquid refluxed 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 wastewater inlet of the first anoxic tank 1. The stable effluent refers to that the concentrations of COD, ammonia nitrogen, total nitrogen and total phosphorus in the effluent fluctuate by no more than 10% relative to the average concentrations of COD, ammonia nitrogen, total nitrogen and total phosphorus within 13 consecutive days.

[0058] It should be noted that the present embodiment is a further improvement based on the patent with the application number 202411483993.2 and the 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 the application number 202411483993.2 and the patent name of Highway Service Area Wastewater Treatment Device and Method Based on AOOA-MBBR Process. The attached Figure 3 to the attached Figure 9 The 0th day in the first step refers to the 0th day after the hydraulic retention time is shortened to 20h, the first replacement of the biofilm anammox bacteria filler 5 is on the 37th day, the second replacement of the biofilm anammox bacteria filler 5 is on the 41st day, the anammox bacteria filler placement position in the first anoxic tank 1 is opposite to the reflux nitrification liquid effluent port, which reduces the influence of dissolved oxygen carried in the reflux nitrification liquid on the anammox bacteria, and the anammox bacteria filler is concentrated in three places to form an aggregation effect, which is conducive to the function of the anammox bacteria. The anammox bacteria filler placement position in the first aerobic tank 2 and the second aerobic tank 3 is close to the four corners (the aeration device 8 is located at the center position), the anammox bacteria filler is far away from the aeration device 8, which reduces the influence of dissolved oxygen on the anammox bacteria, and forms an aggregation effect, which is conducive to the function of the anammox bacteria. The anammox bacteria filler placement position in the second anoxic tank 4 is opposite to the connection port between the second aerobic tank 3 and the second anoxic tank 4, which reduces the influence of dissolved oxygen carried in the effluent of the second aerobic tank 3 on the anammox bacteria, and the anammox bacteria filler is concentrated in three places to form an aggregation effect, which is conducive to the function of the anammox bacteria. The stable stage of the fourth step refers to the period from the 69th day to the 81st day. Manganese (manganese sulfate) is added from the 57th day, and the dosage is gradually increased to 3.5mg / L according to the effluent phosphorus concentration.

[0059] Wherein, in the biofilm anammox bacteria filler 5, the anammox bacteria are grown on the solid filler 5, which can be but not limited to 0.2g-0.3g / g.

[0060] Next, the wastewater treatment method involved in the above embodiment is introduced in detail from the principle aspect.

[0061] Aiming at the characteristics of the extremely low ratio of carbon to nitrogen (COD / TN=1.67-1.70) of the wastewater in the expressway service area, a method of treating the wastewater in the expressway service area based on the enhanced AOOA-MBBR is developed. The hydrolytic bacteria, denitrifying bacteria and anammox bacteria are inoculated on the filler 5 in the first anoxic tank 1. After the influent and the nitrated liquid from the second aerobic tank 3 are mixed on the upper part of the filler 5, they flow through the filler 5. The denitrifying bacteria attached on the filler 5 first reduce the nitrate nitrogen in the backflow nitrated liquid to nitrite nitrogen by using the easily degradable organic matter in the influent as the carbon source. The anammox bacteria reduce the nitrite nitrogen to nitrogen by using the ammonia nitrogen in the influent as the electron acceptor. The residual nitrite nitrogen is further denitrified to nitrogen by the denitrifying bacteria by using the organic matter or the hydrolysis product of the refractory organic matter in the influent as the carbon source. Under the condition of the serious shortage of the carbon source, the high-efficiency hydrolytic bacteria are produced on the filler 5 after long-term cultivation and domestication. The high-efficiency hydrolytic bacteria attached on the filler 5 can hydrolyze the refractory organic matter in the influent to the easily degradable organic matter, thereby providing the carbon source for the denitrification. The biofilm falling off from the filler 5 can also be hydrolyzed to the easily degradable organic matter by the high-efficiency hydrolytic bacteria, thereby providing the carbon source for the denitrification. In addition, the COD removal effect is strengthened after the filler 5 with the anammox bacteria attached thereon is replaced. The concentration of the COD in the first anoxic tank 1 is obviously reduced from the average of 19.25 mg / L (the range is 17.50 mg / L-20.82 mg / L) to the average of 13.58 mg / L (the range is 12.40 mg / L-14.62 mg / L), which can prove the above-mentioned point. The reason is that the filler 5 with the anammox bacteria attached thereon not only has the anammox bacteria attached thereon, but also has a certain amount of hydrolytic bacteria and denitrifying bacteria attached thereon. Since the generation period of the anammox bacteria is very long, the sludge is not discharged during the anammox bacteria biofilm formation process, and the dead microorganisms are hydrolyzed and then used as the carbon source for the denitrification. Therefore, the filler 5 with the anammox bacteria, high-efficiency hydrolytic bacteria and denitrifying bacteria attached thereon can further degrade the refractory organic matter in the first anoxic tank 1.

[0062] The outer layer of the biofilm on the filler 5 in the first aerobic tank 2 is mainly composed of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) by controlling the dissolved oxygen in the first aerobic tank 2 at about 0.2 mg / L, and the inner layer of the biofilm on the filler 5 is mainly composed of anammox bacteria, high-efficiency hydrolysis bacteria and denitrifying bacteria, so as to realize denitrification in the forms of anammox, short-cut denitrification-anammox, short-cut nitrification-denitrification and simultaneous nitrification-denitrification. The AOB in the outer layer of the biofilm on the filler 5 in the first aerobic tank 2 oxidizes the ammonia nitrogen in the effluent from the first anoxic tank 1 to nitrite nitrogen, the anammox bacteria oxidize the ammonia nitrogen in the effluent from the first anoxic tank 1 to nitrogen gas by taking the nitrite nitrogen produced in the ammonia oxidation as an electron acceptor, thereby realizing anammox denitrification; the denitrifying bacteria reduce the nitrite nitrogen to nitrogen gas by taking the hydrolysis products of the refractory organic matter or the hydrolysis products of the shed biofilm as a carbon source, thereby realizing short-cut nitrification-denitrification denitrification; meanwhile, the NOB further oxidize part of the nitrite nitrogen to nitrate nitrogen, the denitrifying bacteria reduce the nitrate nitrogen to nitrite nitrogen by taking the hydrolysis products of the refractory organic matter or the hydrolysis products of the shed biofilm as a carbon source, the anammox bacteria oxidize the ammonia nitrogen in the effluent from the first anoxic tank 1 to nitrogen gas by taking the nitrite nitrogen produced in the nitrate nitrogen denitrification as an electron acceptor, thereby realizing short-cut denitrification-anammox denitrification; the nitrite nitrogen produced in the nitrate nitrogen denitrification is further denitrified to nitrogen gas by the denitrifying bacteria, thereby realizing simultaneous nitrification-denitrification denitrification. The total nitrogen in the first aerobic tank 2 is greatly reduced 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), which proves that the total nitrogen is removed through anammox, short-cut denitrification-anammox, short-cut nitrification-denitrification and simultaneous nitrification-denitrification. In addition, the COD is only reduced from an average of 13.58 mg / L (range: 12.40 mg / L-14.62 mg / L mg / L) to an average of 11.66 mg / L (range: 10.51 mg / L-12.73 mg / L), which further proves the removal mode of the total nitrogen; because the removal of the total nitrogen through anammox does not require a carbon source, the removal of 1 mg of total nitrogen (ammonia nitrogen+nitrate nitrogen) through short-cut denitrification-anammox theoretically only needs to consume 0.74 mg of COD, and the removal of 1 mg of total nitrogen through short-cut nitrification-denitrification theoretically only needs to consume 1.72 mg of COD.

[0063] The dissolved oxygen in the second aerobic tank 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 anammox bacteria, high-efficiency hydrolysis bacteria and denitrifying bacteria is formed on the inner layer of the biofilm on the filler 5, realizing anammox, short-cut denitrification anammox, short-cut nitrification denitrification, simultaneous nitrification denitrification and other ways of nitrogen removal. The first aerobic tank 2 and the second aerobic tank 3 are set for different purposes, the first aerobic tank 2 is mainly aimed at removing total nitrogen, and part of the ammonia nitrogen is oxidized to nitrate nitrogen, so the dissolved oxygen in the first aerobic tank 2 is controlled at about 0.2 mg / L. The second aerobic tank 3 is mainly aimed at completing the nitrification of ammonia nitrogen, and achieves the purpose of convenient operation, while removing part of the total nitrogen, so the dissolved oxygen in the second aerobic tank 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, different proportions of aerobic AOB, NOB, anoxic anammox bacteria, denitrifying bacteria and high-efficiency hydrolysis bacteria in the biofilm. The AOB on the outer layer of the filler 5 in the second aerobic tank 3 oxidizes the ammonia nitrogen in the effluent of the first aerobic tank 2 to nitrite nitrogen, the anammox bacteria take 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, realizing anammox denitrification; the denitrifying bacteria take the hydrolysis products of refractory organic matter or the hydrolysis products of shed biofilm as carbon source to reduce the nitrite nitrogen to nitrogen, realizing short-cut nitrification denitrification; at the same time, the NOB further oxidize part of the nitrite nitrogen to nitrate nitrogen, the denitrifying bacteria take the hydrolysis products of refractory organic matter or the hydrolysis products of shed biofilm as carbon source to reduce the nitrate nitrogen to nitrite nitrogen, the anammox bacteria take the nitrite nitrogen produced by the denitrification of nitrate nitrogen as an electron acceptor to oxidize the ammonia nitrogen in the effluent of the first aerobic tank 2 to nitrogen, realizing short-cut denitrification anammox; the nitrite nitrogen produced by the denitrification of nitrate nitrogen is further denitrified to nitrogen by the denitrifying bacteria, realizing simultaneous nitrification denitrification. In addition, due to the higher concentration of dissolved oxygen in the second aerobic tank 3, the ammonia nitrogen in the effluent of the second aerobic tank 3 is reduced to an average of 0.73 mg / L (range: 0.65 mg / L-0.80 mg / L), achieving the goal of ammonia nitrogen nitrification. The total nitrogen in the second aerobic tank 3 is significantly reduced 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 is removed by anammox, short-cut denitrification anammox, short-cut nitrification denitrification, simultaneous nitrification denitrification and other ways. In addition, COD is only reduced 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 total nitrogen removal method.

[0064] In the second anoxic tank 4, since the total nitrogen in the effluent of the second aerobic tank 3 is mainly in the form of nitrate (about 8 mg / L (range 8.12 mg / L-8.28 mg / L), nitrite about 0.9 mg / L (range 0.81 mg / L-1.01 mg / L), ammonia nitrogen about 0.7 mg / L (range 0.65 mg / L-0.80 mg / L), and organic nitrogen about 1 mg / L (range 0.46 mg / L-1.69 mg / L), and the COD in the effluent of the second aerobic tank 3 is only 10.25 mg / L (range 9.49 mg / L-10.95 mg / L); the carbon source in the effluent of the second aerobic tank 3 is limited and cannot meet the demand for carbon source for denitrification. In addition, the total phosphorus in the effluent of the second aerobic tank 3 is 1.89 mg / L-1.99 mg / L, which cannot meet the discharge requirement of total phosphorus ≤0.5 mg / L. In view of this, about 1% of the influent with manganese sulfate is directly pumped into the second anoxic tank 4, so that the dosage of manganese is about 3.5 mg / L; and the biofilm anaerobic ammonia oxidation bacteria carrier 5 is replaced, so that short-cut denitrification, anaerobic ammonia oxidation, denitrification, and removal of phosphorus by precipitation of phosphate with manganese are carried out in the second anoxic tank 4. Efficient hydrolytic bacteria, denitrifying bacteria, and anaerobic ammonia oxidation bacteria are cultured and domesticated on the carrier 5 in the second anoxic tank 4. The denitrifying bacteria reduce the nitrate in the effluent of the second aerobic tank 3 to nitrite using the easily degradable organic matter in the influent as the carbon source, and the anaerobic ammonia oxidation bacteria reduce the nitrite produced by the denitrification of nitrate to nitrogen gas using the ammonia nitrogen in the influent as the electron donor, and part of the nitrite is further denitrified to nitrogen gas by the denitrifying bacteria using the organic matter or the hydrolysis products of the refractory organic matter in the influent as the carbon source. Efficient hydrolytic bacteria are also domesticated in the second anoxic tank 4, which can hydrolyze the refractory organic matter in the influent to easily degradable organic matter to provide carbon source for denitrification. The biofilm shed from the carrier 5 can also be hydrolyzed to easily degradable organic matter by the efficient hydrolytic bacteria to provide carbon source for denitrification. The manganese in the influent directly pumped into the second anoxic tank 4 can react with phosphate to generate manganese phosphate precipitate; the generated manganese phosphate can be adsorbed by the biofilm on the carrier 5 in the second anoxic tank 4 to achieve phosphorus removal Figure 10 It is illustrated that manganese and phosphorus react by precipitation, and the generated manganese phosphate precipitate adheres to the carrier, and the precipitate does not flow out with the effluent, so that secondary pollution is not caused.

[0065] Based on the above ideal embodiments according to the present application, the related personnel can make various changes and modifications without deviating from the technical concept of the present application. The technical scope of the present application is not limited to the contents in the specification, and must be determined according to the scope of the claims.

Claims

1. A method for treating highway service area wastewater based on anaerobic ammonia oxidation (AOOA) -enhanced MBBR, characterized in that, The method comprises: Step 1: Preparing 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) connected in sequence, each filled with filler (5), and the first aerobic tank (2) and the second aerobic tank (3) are each provided with an aeration device (8); the second aerobic tank (3) is connected to the first anoxic tank (1) through a reflux pipe provided with a reflux power assembly (6); Step 2: Starting the reactor and inoculating bacteria: Highway service area wastewater 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 h; the nitrified liquid is refluxed from the second aerobic tank (3) to the first anoxic tank (1) at a reflux ratio of 200%; After the effluent has been stably operated for a predetermined time, the hydraulic retention time is gradually shortened to 36 h, 24 h, and 20 h; Step 3: Anaerobic ammonia oxidation enhancement: After the effluent has been stably operated for a predetermined time, the filler (5) with a biofilm of anaerobic ammonia oxidation bacteria is used to replace part of the filler (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; part of the highway service area wastewater is directly pumped into the second anoxic tank (4) after adding manganese sulfate; Step 4: After the effluent is stable, enter the stable stage. 2.The method for treating highway service area wastewater based on anaerobic ammonia oxidation (AOOA) -enhanced MBBR according to claim 1, characterized in that, In step 3, during the replacement of the filler (5), the replacement is carried out in two times, 4% of the filler (5) in each tank is replaced in the first time, and 2% of the filler (5) in each tank is replaced in the second time. 3.The method for treating highway service area wastewater based on anaerobic ammonia oxidation (AOOA) -enhanced MBBR according to claim 1, characterized in that, In step 3, 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 method for treating highway service area wastewater based on anaerobic ammonia oxidation (AOOA) -enhanced MBBR according to claim 1, characterized in that, The first anoxic tank (1), the first aerobic tank (2), the second aerobic tank (3), and the second anoxic tank (4) each take the volume of the added filler (5) as the effective volume.

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

6. The method for treating highway service area wastewater based on anaerobic ammonia oxidation enhanced AOOA-MBBR according to claim 1, characterized in that, The carbon-nitrogen ratio COD / TN of the highway service area wastewater is 1.67-1.70.

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