Integrated biological treatment process for emulsion explosive production wastewater

Abstract

The application discloses a kind of biological integrated treatment processes of emulsion explosive production wastewater.The process includes four sections of short-path denitrification-anaerobic ammonia oxidation-nitrification-sulfur autotrophic denitrification, first emulsion explosive production wastewater is pumped into short-path denitrification section, effective accumulation of nitrous nitrogen is realized;Short-path denitrification effluent enters anaerobic ammonia oxidation section, and anaerobic ammonia oxidation bacteria are used to remove nitrous nitrogen in short-path denitrification effluent and ammonia nitrogen in influent simultaneously;Anaerobic ammonia oxidation effluent enters nitrification section, and part of ammonia nitrogen is converted into nitrate nitrogen by nitrification;Nitrification effluent enters sulfur autotrophic denitrification section, and sulfur autotrophic denitrification is used to remove nitrate nitrogen in wastewater by using elemental sulfur as electron donor, so as to realize standard discharge of wastewater.The biological integrated treatment process used in the application reduces the amount of carbon source, and effectively saves the cost of wastewater treatment based on autotrophic biological denitrification technology.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology and relates to a biological integrated treatment process for emulsion explosive production wastewater, specifically a short-cut denitrification-anaerobic ammonia oxidation-nitrification-sulfur autotrophic denitrification integrated treatment process for emulsion explosive production wastewater. Background Technology

[0002] Emulsion explosives possess advantages such as good water resistance, excellent explosive performance, low mechanical sensitivity, and high safety, and their cost is lower than that of water-gel explosives, leading to their widespread application in the domestic and international civil explosives industry. However, due to industry secrecy and other reasons, the foundation for environmental technology research and development in the explosives, pyrotechnics, and civil explosives industries is relatively weak, severely hindering their healthy and green development. In recent years, with increasingly stringent environmental requirements, the risk of environmental accountability for enterprises has further increased, making the construction of wastewater treatment systems urgently needed.

[0003] The main pollutants in emulsion explosive wastewater include ammonium nitrate and sodium nitrate. The difficulty in its treatment lies in the high levels of ammonia nitrogen and nitrate in the wastewater. Nitrogenous pollutants in the wastewater can be removed by physical, chemical, and biological methods. Compared with physical and chemical denitrification methods, biological denitrification is an environmentally friendly and sustainable denitrification process and is currently the mainstream wastewater denitrification technology. Traditional biological denitrification processes include nitrification and denitrification. The nitrification process involves nitrifying bacteria converting ammonia nitrogen into nitrate nitrogen in an aerobic environment, while the denitrification process involves denitrifying microorganisms using organic matter as electron donors to reduce nitrate nitrogen into nitrogen gas in an anaerobic environment. Currently, after filtration and oil separation pretreatment, emulsion explosive wastewater is mainly treated using a combination of chemical treatment and biological treatment. Chemical treatment is relatively more expensive than biological treatment, and biological treatment is a traditional nitrification-denitrification biological denitrification process with a large demand for carbon sources (Wang Chunling et al. Research on wastewater treatment technology for emulsion explosive production. Energy and Environmental Protection, 2007, 21(4):30-32). The "magnesium ammonium phosphate precipitation method (MAP method)-biochemical method" was used to treat emulsified explosive wastewater. The biochemical method adopted the AO process, which has high reagent costs and large sludge production, resulting in high wastewater treatment costs (Zhou Liangqing et al. Application of MAP chemical precipitation method in the treatment of re-emulsified explosive wastewater. Chemical Industry Management, 2018).

[0004] Traditional biological nitrogen removal technologies face challenges such as high energy consumption (e.g., high investment costs) and large sludge production, necessitating the development of environmentally friendly and low-cost biological nitrogen removal technologies for wastewater. Anaerobic ammonia oxidation (AAO) is a novel biological nitrogen removal process. Under anaerobic conditions, AAO bacteria use ammonia nitrogen as an electron donor to reduce nitrite nitrogen to nitrogen gas. Compared to traditional nitrification-denitrification processes, AAO significantly reduces aeration energy consumption, eliminates the need for organic carbon sources, and produces low sludge production, making it a promising technology with potential applications. However, the key to the successful application of AAO lies in the stable and efficient supply of nitrite nitrogen. Short-cut denitrification can control nitrate nitrogen reduction to the nitrite stage, achieving stable nitrite accumulation. Short-cut denitrification coupled with AAO provides a new approach for low-energy nitrogen removal from wastewater (Lai et al., Research Progress on Short-cut Denitrification / Anaerobic Ammonia Oxidation Process. Environmental Pollution and Control, 2021), but this process faces numerous challenges, including water quality fluctuations.

[0005] Therefore, the development of emulsion explosive wastewater treatment technologies and processes that offer stable treatment results, are easy to operate, and have low treatment costs has become an urgent problem to be solved in the civil explosives industry. Summary of the Invention

[0006] The purpose of this invention is to provide a low-cost, high-efficiency biological integrated treatment process for wastewater from the production of emulsion explosives.

[0007] The technical solution for achieving the objective of this invention is as follows:

[0008] The integrated biological treatment process for wastewater from emulsion explosives production includes four stages: short-cut denitrification, anaerobic ammonium oxidation, nitrification, and sulfur autotrophic denitrification. The specific steps are as follows:

[0009] Step 1: Pump the wastewater from the production of emulsion explosives into the short-cut denitrification chemical section, adjust the pH to 8.0-8.5, inoculate the short-cut denitrification reactor with short-cut denitrification sludge, and under the action of short-cut denitrification microorganisms, reduce the nitrate nitrogen in the wastewater to nitrite nitrogen in a short-cut manner.

[0010] Step 2: The short-cut denitrification effluent enters the anaerobic ammonia oxidation section. Anaerobic ammonia oxidation sludge is inoculated into the anaerobic ammonia oxidation reactor. Under the action of anaerobic ammonia oxidation bacteria, pollutants such as ammonia nitrogen and nitrite nitrogen in the water are degraded and removed.

[0011] Step 3: The effluent from the anaerobic ammonia oxidation enters the nitrification section. Nitrifying sludge is inoculated into the nitrification reactor, and nitrifying microorganisms oxidize all the remaining ammonia nitrogen and nitrite nitrogen in the wastewater into nitrate nitrogen in an aerobic environment.

[0012] Step 4: The nitrified effluent enters the sulfur autotrophic denitrification section. Sulfur autotrophic denitrification sludge is inoculated into the sulfur autotrophic denitrification reactor, and sulfur-based packing material is filled into the sulfur autotrophic denitrification reactor as an electron donor. Under the action of sulfur autotrophic denitrification microorganisms, nitrate nitrogen in the wastewater is removed.

[0013] Preferably, in step 1, the hydraulic retention time of the short-cut denitrification section is 24-48 hours.

[0014] Preferably, in step 1, the inoculum concentration of the short-cut denitrification sludge is 4000-6000 mg / L.

[0015] Preferably, in step 1, 2 or 3, the packing material in the reactor is polyurethane packing material; in step 1 or 2, the packing ratio is 0.3-0.6, and in step 3, the packing ratio is 0.5-0.7.

[0016] Preferably, in step 2, the hydraulic retention time of the anaerobic ammonia oxidation section is 24-48 hours.

[0017] Preferably, in step 2, the inoculation concentration of the anaerobic ammonia oxidation sludge is 4000-6000 mg / L.

[0018] Preferably, in step 3, the hydraulic retention time in the nitration section is 12-36 hours.

[0019] Preferably, in step 3, the inoculation concentration of the nitrifying sludge is 4000-6000 mg / L.

[0020] Preferably, in step 4, the hydraulic retention time of the sulfur autotrophic denitrification chemical section is 48–72 h.

[0021] Preferably, in step 4, the inoculum concentration of the sulfur autotrophic denitrification sludge is 4000-6000 mg / L.

[0022] Preferably, in step 4, the sulfur-based filler is prepared by mixing sulfur powder and shell powder evenly in a weight ratio of 1:1 to 3:1 and then heating and melting them at 180°C. The filling ratio of the sulfur-based filler is 0.3 to 0.8.

[0023] This invention relates to an integrated short-cut denitrification-anaerobic ammonium oxidation-nitrification-sulfur autotrophic denitrification treatment process for emulsion explosive production wastewater, comprising a short-cut denitrification section, an anaerobic ammonium oxidation section, a nitrification section, and a sulfur autotrophic denitrification deep treatment section. In the short-cut denitrification section, short-cut denitrifying microorganisms from inoculated sludge reduce nitrate nitrogen to nitrite nitrogen, achieving effective reduction of nitrate nitrogen and stable accumulation of nitrite nitrogen. In the anaerobic ammonium oxidation section, the nitrite nitrogen produced in the short-cut denitrification section, along with ammonia nitrogen in the influent, is utilized by anaerobic ammonium oxidizing bacteria, using ammonia nitrogen as an electron donor and nitrite nitrogen as an electron acceptor, achieving effective removal of nitrogen-containing pollutants. In the nitrification section, nitrifying sludge is inoculated, and aeration ensures an aerobic environment, oxidizing the remaining ammonia nitrogen and nitrite nitrogen from the anaerobic ammonium oxidation section back to nitrate nitrogen. The effluent from the nitrification tank enters the sulfur autotrophic denitrification section, where sulfur autotrophic denitrification sludge is inoculated and sulfur-based packing is filled as an electron donor. Nitrate nitrogen is removed through sulfur autotrophic denitrification to achieve compliant discharge.

[0024] Compared with the prior art, the present invention has the following significant advantages:

[0025] (1) The application of short-cut denitrification technology significantly reduces the amount of organic carbon source added. Anaerobic ammonia oxidation technology is an environmentally friendly denitrification process that reduces aeration energy consumption, sludge production, and effectively reduces wastewater treatment costs.

[0026] (2) Based on the sulfur autotrophic denitrification process, the addition of sulfur-based filler has the ability to release electrons sustainably, without the need for external carbon source addition, and is economical and efficient. It realizes the biological denitrification treatment of emulsion explosive production wastewater and effectively saves wastewater treatment costs.

[0027] (3) The integrated treatment process of short-range denitrification-anaerobic ammonia oxidation-nitrification-sulfur autotrophic denitrification for emulsion explosive production wastewater can achieve stable compliance with Class A discharge standards for emulsion explosive production wastewater. Attached Figure Description

[0028] Figure 1 These are images showing the effects of treatment with sulfur-based materials in different proportions.

[0029] Figure 2 This is a diagram of the effluent from the start-up of a short-cut denitrification process.

[0030] Figure 3 This is a diagram of sulfur-based particulate packing.

[0031] Figure 4 This is a process flow diagram of the wastewater treatment system for emulsion explosives production, in which (1) is the inlet pool; (2) is the short-cut denitrification pool; (3) is the anaerobic ammonia oxidation pool; (4) is the nitrification pool; (5) is the sulfur autotrophic denitrification pool; (6) is the peristaltic pump; (7) is the air pump; and (8) is the gas flow meter.

[0032] Figure 5 This is the effluent diagram of a combined short-cut denitrification-anaerobic ammonium oxidation-nitrification-sulfur autotrophic denitrification process.

[0033] Figure 6 This is the effluent diagram of the combined process of short-cut denitrification-anaerobic ammonium oxidation-short-cut denitrification-anaerobic ammonium oxidation. Detailed Implementation

[0034] The present invention will now be further described with reference to specific embodiments and accompanying drawings.

[0035] The terminology used in this invention, unless otherwise specified, generally has the meanings commonly understood by those skilled in the art. The invention is further described in detail below with reference to specific embodiments and data. It should be understood that these embodiments are merely illustrative and not intended to limit the scope of the invention in any way. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0036] In the following embodiments, the simulated wastewater composition is as follows:

[0037] The inorganic salt culture medium consists of the following: KH₂PO₄ (0.029 g / L), MgSO₄·7H₂O (0.3 g / L), CaCl₂·2H₂O (0.136 g / L), KHCO₃ (1.2 g / L), and trace element solution I (1 mL / L). Trace element I consists of: EDTA (5 g / L), FeSO₄·7H₂O (5 g / L), and trace element II (1 mL / L). Trace element II composition: EDTA (15 g / L), H3BO3 (0.011 g / L), MnCl2·4H2O (0.99 g / L), CuSO4·5H2O (0.25 g / L), ZnSO4·7H2O (0.43 g / L), NiCl2·6H2O (0.19 g / L), Na2MoO4·2H2O (0.22 g / L), CoCl2·6H2O (0.24 g / L), NaSeO4·10H2O (0.21 g / L). The amounts of ammonium chloride, sodium nitrate, and sodium acetate are added according to experimental needs.

[0038] Example 1

[0039] Sulfur-based granular packing material was prepared using sulfur powder and shell powder in a sulfur autotrophic denitrification reactor. Since the wastewater becomes acidic during the sulfur autotrophic reaction, shell powder was added as a pH buffer. The shell powder was ground and sieved (100 mesh). Sulfur powder and shell powder were mixed evenly in a shaker at weight ratios of 1:0, 1:1, 1.5:1, 2:1, and 3:1. The mixture was then melted on a heating plate at 180℃ and poured into a mold to form the sulfur-based granular packing material. The nitrate nitrogen removal performance of the sulfur-based granular packing material with different ratios was as follows: Figure 1 As shown, the influent nitrate nitrogen concentration was 50 mg / L. The nitrate nitrogen removal effect in the reactor packed with 1:1 sulfur-based granular packing was significantly better than that of other ratios of sulfur-based granules. Its nitrate nitrogen removal rate was the fastest, and nitrate nitrogen was undetectable in the effluent after 72 hours.

[0040] Example 2

[0041] (1) Start-up of the short-cut denitrification reactor

[0042] Anoxic sludge (4500 mg / L) was inoculated into a short-cut denitrification reactor. Polyurethane packing material was placed inside the reactor for microbial attachment. The influent pH was 8.3, and the temperature was room temperature. The nitrogenous pollutant in the influent was nitrate nitrogen, and sodium acetate, an organic carbon source, was used as the electron donor. Based on the nitrate nitrogen removal and nitrite nitrogen accumulation effects, the concentration of nitrate nitrogen in the influent was gradually increased, and the C / N ratio was gradually decreased (4→3→2.8→2.6), thereby improving the conversion rate of nitrate nitrogen to nitrite nitrogen and achieving effective accumulation of nitrite nitrogen in the short-cut denitrification reactor. Figure 2 The nitrate nitrogen removal rate (NRE) remains above 80%, while the nitrite nitrogen accumulation rate increases as the C / N ratio decreases, reaching over 50%.

[0043] (2) Start-up of the anaerobic ammonia oxidation reactor

[0044] Polyurethane packing material was placed inside the reactor for microbial attachment, and mature anaerobic ammonia oxidation granular sludge (4000 mg / L) was inoculated. The concentrations of ammonia nitrogen and nitrite nitrogen in the influent were adjusted according to the nitrogen removal effect. The influent ammonia nitrogen and nitrite nitrogen were added at a ratio of 1:1.32, with the concentrations of ammonia nitrogen (100→150→200→250) and nitrite nitrogen gradually increasing. The HRT was set to 36 h, and the anaerobic ammonia oxidation reactor was successfully started up.

[0045] (3) Start-up of the nitration reactor

[0046] The influent to the nitrification reactor is the effluent from the primary anaerobic ammonia oxidation process, and the inoculated sludge is aerobic sludge (5000 mg / L). Polyurethane packing is placed inside the reactor for microbial attachment, and the HRT is set to 24 h.

[0047] (4) Preparation of sulfur-based materials

[0048] Sulfur powder and shell powder are mixed in a 1:1 ratio and heated to melt on a heating plate at 180℃ to produce sulfur-based granules. The shell powder is ground and sieved (100 mesh). Before heating, the sulfur powder and shell powder are mixed evenly using a vibrator. The sulfur-based granule filler is as follows: Figure 3 As shown.

[0049] (5) Start-up of the sulfur autotrophic denitrification (SAD) reactor

[0050] When sulfur-based autotrophic denitrification sludge was inoculated and sulfur-based granular packing was used as an electron donor, it was observed that almost all nitrate nitrogen was removed, and the sulfur-based autotrophic denitrification was successfully started.

[0051] Example 3

[0052] Wastewater simulation was conducted using pollutant indicators from a certain civil explosives industry production wastewater as a reference. The wastewater's chemical oxygen demand (COD) concentration ranged from 10 to 50 mg / L, ammonia nitrogen from 250 to 320 mg / L, nitrite nitrogen from 5 to 20 mg / L, and nitrate nitrogen from 250 to 300 mg / L. The combined process flow of "short-cut denitrification-anaerobic ammonium oxidation-nitrification-sulfur autotrophic denitrification" is as follows: Figure 4 As shown.

[0053] Short-cut denitrifying bacteria are used to reduce nitrate nitrogen in wastewater to the nitrite stage. The influent pH is adjusted to 8.0–8.5 with sodium hydroxide, and sodium acetate is added to maintain a C / N ratio of 2. The hydraulic retention time (HRT) is set at 30 hours. The biological action of the short-cut denitrifying bacteria achieves partial reduction of nitrate nitrogen and effectively accumulates nitrite nitrogen. In the anaerobic ammonia oxidation (AMO) section, anaerobic ammonia oxidizing bacteria remove both ammonia nitrogen from the wastewater and the nitrite nitrogen accumulated in the short-cut denitrification section. The HRT is 30 hours, achieving the oxidative degradation of nitrogenous pollutants. In the nitrification section, aerobic sludge is inoculated, and the reactor is filled with polyurethane packing material for nitrifying bacteria to attach to. The HRT is 48 hours. The anaerobic ammonia oxidation effluent is used as the nitrification influent, and nitrifying bacteria convert all residual ammonia nitrogen and nitrite nitrogen in the wastewater into nitrate nitrogen. The effluent from the nitrification stage enters the sulfur autotrophic denitrification reaction tank, which is filled with sulfur-based granular packing material. The sulfur-based granules are made by heating and melting sulfur powder and shell powder in a 1:1 ratio. The HRT is set to 72h. Sulfur autotrophic denitrification microorganisms are used to remove nitrate nitrogen from the wastewater to achieve compliant discharge.

[0054] An additional carbon source is added to the short-cut denitrification tank, and the influent C / N ratio is set to 2 to ensure the effective accumulation of nitrite nitrogen in the short-cut denitrification reaction.

[0055] Anaerobic ammonia oxidation reactor is inoculated with anaerobic ammonia oxidation granular sludge. Anaerobic ammonia oxidation bacteria remove ammonia nitrogen and nitrite nitrogen from wastewater without aeration or external carbon source, achieving efficient denitrification.

[0056] In the nitrification reactor, ammonia nitrogen and nitrite nitrogen are completely oxidized into nitrate nitrogen by nitrifying bacteria. At this time, the wastewater is composed of nitrate nitrogen.

[0057] The effluent from the nitrification tank enters the sulfur autotrophic denitrification reactor. The sulfur-based material continuously releases electrons in the reactor, and under the action of sulfur autotrophic denitrifying bacteria, the nitrate nitrogen in the wastewater is converted into nitrogen gas, thus achieving the standard discharge.

[0058] Based on the analysis of influent and effluent data for pollutants in the wastewater, the short-cut denitrification-anaerobic ammonium oxidation-nitrification-sulfur autotrophic denitrification process was confirmed to effectively degrade ammonia nitrogen and nitrate nitrogen in the wastewater. Figure 5 As shown, the effluent contains 0% ammonia nitrogen and 0% nitrite nitrogen, and the effluent concentration of nitrate nitrogen is less than 10 mg / L. The total nitrogen removal rate is over 95%, and the effluent can meet the Class A discharge standard.

[0059] The removal efficiency of each stage under stable operation conditions of the combined process of "short-cut denitrification-anaerobic ammonium oxidation-nitrification-sulfur autotrophic denitrification" is shown in Table 1.

[0060] Table 1. Effluent water quality indicators of each stage of the combined process.

[0061]

[0062] In summary, the "short-cut denitrification-anaerobic ammonia oxidation-nitrification-sulfur autotrophic denitrification" biological treatment process requires less carbon source input and has lower investment costs compared to traditional biological nitrogen removal processes. The C / N ratio in the short-cut denitrification stage is 2, significantly lower than in traditional denitrification processes, effectively reducing carbon source input. In the short-cut denitrification process, nitrate nitrogen is converted to nitrite nitrogen by microorganisms, with an accumulation rate exceeding 80%. The generated nitrite nitrogen can provide the electron acceptor required for the anaerobic ammonia oxidation reaction. The nitrite nitrogen produced by short-cut denitrification, along with ammonia nitrogen in the wastewater, is converted into nitrogen gas by anaerobic ammonia oxidizing bacteria, while a small amount of nitrate nitrogen is also produced. To prevent instability of anaerobic ammonia oxidizing bacteria when encountering adverse environments during actual operation, a nitrification process is adopted to convert all residual ammonia nitrogen and nitrite nitrogen in the anaerobic ammonia oxidation effluent into nitrate nitrogen. The main pollutant in the wastewater is nitrate nitrogen. Then, the nitrate nitrogen in the wastewater is removed through a sulfur autotrophic denitrification process. Finally, the nitrate nitrogen in the effluent is <10mg / L, and the wastewater meets the Class A discharge standard.

[0063] Comparative Example 1

[0064] Comparative Example 1 employed a combined process of "short-cut denitrification-anaerobic ammonium oxidation-short-cut denitrification-anaerobic ammonium oxidation." The influent water quality and operating parameters of each stage were the same as in Example 1. The difference was that a secondary short-cut denitrification stage followed the anaerobic ammonium oxidation stage to partially reduce the nitrate nitrogen produced during the primary anaerobic ammonium oxidation process, converting it into nitrite nitrogen. The ammonia nitrogen and nitrite nitrogen were then removed through the secondary anaerobic ammonium oxidation process. The removal efficiency of each stage under stable operating conditions is shown in [the figure]. Figure 6 As shown, the effluent ammonia nitrogen concentration was high (>100 mg / L), and the nitrate nitrogen produced in the secondary anaerobic ammonia oxidation stage could not be removed. The effluent nitrate nitrogen concentration increased from 59.74 mg / L to 126.71 mg / L, and the total nitrogen removal rate was approximately 50%. Therefore, the wastewater could not meet discharge standards.

Claims

1. A biological integrated treatment process for wastewater from the production of emulsion explosives, characterized in that, It includes four stages: short-cut denitrification, anaerobic ammonium oxidation, nitrification, and sulfur autotrophic denitrification. The specific steps are as follows: Step 1: Pump the wastewater from emulsion explosive production into the short-cut denitrification section, adjust the pH to 8.0~8.5, add an additional carbon source, set the influent C / N ratio to 2, inoculate the short-cut denitrification reactor with short-cut denitrification sludge, and under the action of short-cut denitrification microorganisms, reduce nitrate nitrogen in the wastewater to nitrite nitrogen in a short-cut manner; the chemical oxygen demand (COD) concentration of the wastewater from emulsion explosive production ranges from 10~50 mg / L, the ammonia nitrogen concentration ranges from 250~320 mg / L, the nitrite nitrogen concentration ranges from 5~20 mg / L, and the nitrate nitrogen concentration ranges from 250~300 mg / L. Step 2: The short-cut denitrification effluent enters the anaerobic ammonia oxidation section. Anaerobic ammonia oxidation sludge is inoculated into the anaerobic ammonia oxidation reactor. Under the action of anaerobic ammonia oxidation bacteria, the ammonia nitrogen and nitrite nitrogen pollutants in the water are degraded and removed. Step 3: The effluent from the anaerobic ammonia oxidation enters the nitrification section. Nitrifying sludge is inoculated into the nitrification reactor, and nitrifying microorganisms oxidize all the remaining ammonia nitrogen and nitrite nitrogen in the wastewater into nitrate nitrogen in an aerobic environment. Step 4: The nitrified effluent enters the sulfur autotrophic denitrification section. Sulfur autotrophic denitrification sludge is inoculated into the sulfur autotrophic denitrification reactor, and sulfur-based packing material is filled into the sulfur autotrophic denitrification reactor as an electron donor. Under the action of sulfur autotrophic denitrification microorganisms, nitrate nitrogen in the wastewater is removed.

2. The integrated biological treatment process according to claim 1, characterized in that, In step 1, the hydraulic retention time in the short-cut denitrification section is 24-48 hours.

3. The integrated biological treatment process according to claim 1, characterized in that, In step 1, the inoculum concentration of the short-cut denitrification sludge is 4000-6000 mg / L.

4. The integrated biological treatment process according to claim 1, characterized in that, In step 1, 2, or 3, the packing material in the reactor is polyurethane packing material; in step 1 or 2, the packing ratio is 0.3-0.6, and in step 3, the packing ratio is 0.5-0.

7.

5. The integrated biological treatment process according to claim 1, characterized in that, In step 2, the hydraulic retention time in the anaerobic ammonia oxidation section is 24-48 h.

6. The integrated biological treatment process according to claim 1, characterized in that, In step 2, the inoculum concentration of the anaerobic ammonia oxidation sludge is 4000-6000 mg / L.

7. The integrated biological treatment process according to claim 1, characterized in that, In step 3, the hydraulic retention time in the nitration section is 12-36 hours.

8. The integrated biological treatment process according to claim 1, characterized in that, In step 3, the inoculum concentration of the nitrified sludge is 4000-6000 mg / L.

9. The integrated biological treatment process according to claim 1, characterized in that, In step 4, the hydraulic retention time in the sulfur autotrophic denitrification chemical section is 48~72 h.

10. The integrated biological treatment process according to claim 1, characterized in that, In step 4, the inoculum concentration of the sulfur autotrophic denitrification sludge is 4000-6000 mg / L; the sulfur-based filler is made by mixing sulfur powder and shell powder evenly at a weight ratio of 1:1 to 3:1 and then heating and melting them at 180℃, and the filling ratio of the sulfur-based filler is 0.3 to 0.8.

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