Biomineralization / endogenous short-cut denitrification coupled anaerobic ammonium oxidation wastewater treatment system

Abstract

The present invention relates to the field of wastewater treatment technology, and in particular to a biomineralization / endogenous short-cut denitrification coupled anaerobic ammonium oxidation wastewater treatment system. In the anaerobic zone of the biomineralization / endogenous short-cut denitrification reactor, microorganisms absorb organic matter and convert it into PHAs, releasing a large amount of phosphorus. In the anoxic zone, microorganisms use PHAs to convert NO3 ‑ Converted into NO2 ‑ And absorb a large amount of phosphorus. At this time, biomineralization is used to enhance the removal of phosphorus. The effluent from the biomineralization / endogenous short-cut denitrification reactor enters the anaerobic ammonium oxidation reactor to achieve efficient removal of nitrogen in the wastewater. Part of the granular sludge in the sedimentation tank is returned to the anaerobic zone of the biomineralization / endogenous short-cut denitrification reactor, and the other part is dispersed and separated to obtain inorganic hydroxyapatite core and sludge containing high organic matter. On the one hand, phosphorus is recovered and utilized as a resource, and on the other hand, the high-organic matter sludge provides a carbon source for the biomineralization / endogenous short-cut denitrification reactor through fermentation, thereby reducing the amount of excess sludge and making it a resource.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and in particular to a biomineralization / endogenous short-range denitrification coupled anaerobic ammonia oxidation wastewater treatment system. Background Art

[0002] With the increasing problems of water eutrophication and phosphate rock depletion, biological denitrification, phosphorus removal, and phosphorus recovery processes are being widely researched and applied. Traditional biological denitrification and phosphorus removal processes rely on carbon sources, and competition for carbon sources among different microorganisms limits further improvement in total nitrogen and phosphorus removal rates in low-carbon-nitrogen ratio municipal wastewater, and also impose high operating costs. Conventional chemical precipitation phosphorus removal is also detrimental to phosphorus removal and recovery in wastewater with low phosphorus concentrations. Therefore, achieving simultaneous denitrification, phosphorus removal, and phosphorus recovery in a cost-effective manner has become a major challenge in treating low-carbon-nitrogen ratio municipal wastewater.

[0003] Biomineralization, which combines biological transformation with chemical precipitation, has become a research hotspot due to its advantages in energy conservation and consumption reduction. Using biomineralization to induce hydroxyapatite formation within wastewater biological denitrification and phosphorus removal systems could not only address eutrophication but also enable phosphorus recycling.

[0004] Anaerobic ammonium oxidation (NH4 + +NO2 - →N2) As an economical and environmentally friendly wastewater denitrification process, it is considered to be one of the most sustainable biotechnologies. + It is a common pollutant in wastewater, stable NO2 - Supply is the key to the practical application of anaerobic ammonium oxidation; endogenous short-range denitrification (NO3 - →NO2 - ) can provide stable and efficient NO2 for anaerobic ammonium oxidation - Source, promote the promotion and application of anaerobic ammonium oxidation technology. In addition, the presence of polyphosphate and polysaccharide bacteria in endogenous short-range denitrification can effectively remove nitrogen from wastewater while ensuring the efficient removal of phosphorus in wastewater. At the same time, the endogenous short-range denitrification process consumes H + It can create an alkaline environment, providing the necessary conditions for the crystallization of hydroxyapatite and the combination of endogenous short-range denitrification. The induction of hydroxyapatite formation through the biological process of endogenous short-range denitrification not only improves the denitrification and phosphorus removal capacity of wastewater, but also significantly increases the phosphorus recovery rate.

[0005] Based on the challenges and difficulties currently faced in urban domestic wastewater treatment, the wastewater treatment system of the present invention combines endogenous short-range denitrification with biologically induced mineralization, and couples it with the anaerobic ammonia oxidation process, thereby promoting the denitrification and phosphorus removal capabilities of the wastewater treatment system, while achieving efficient phosphorus recovery, which has positive significance for environmental protection and resource recycling. Summary of the Invention

[0006] The purpose of the present invention is to provide a biomineralization / endogenous short-range denitrification coupled anaerobic ammonium oxidation wastewater treatment system to solve the problem that the existing wastewater treatment system has unsatisfactory phosphorus removal effect and is not convenient for phosphorus resource recovery and utilization.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a biomineralization / endogenous short-cut denitrification coupled anaerobic ammonium oxidation wastewater treatment system, comprising a biomineralization / endogenous short-cut denitrification reactor, an anaerobic ammonium oxidation reactor, a sludge ultrasonic dispersion device, a hydrocyclone, and a sludge fermentation tank;

[0008] The biomineralization / endogenous short-cut denitrification reactor includes an anaerobic zone and an anoxic zone. The anaerobic zone is connected to the municipal wastewater inlet tank, and the anoxic zone is connected to the industrial wastewater inlet tank and a drug-adding box. A chemical is added to the anoxic zone through the drug-adding box to induce biomineralization in the anoxic zone, forming endogenous short-cut denitrification granular sludge with hydroxyapatite as the core, thereby achieving phosphorus removal.

[0009] The effluent from the anoxic zone is connected to a sedimentation tank, and the supernatant from the effluent from the sedimentation tank is introduced into an anaerobic ammonium oxidation reactor, where an anaerobic ammonium oxidation reaction occurs to achieve the simultaneous removal of ammonia nitrogen and nitrite nitrogen; a portion of the granular sludge precipitated in the sedimentation tank is returned to the anaerobic zone of the biomineralization / endogenous short-range denitrification reactor to maintain an appropriate sludge concentration, and the other portion is introduced into a sludge ultrasonic dispersion device;

[0010] The ultrasonic sludge dispersing device is provided with an ultrasonic vibrating rod, and is used to disperse inorganic hydroxyapatite cores in granular sludge and sludge containing high organic matter;

[0011] The sludge ultrasonic dispersion equipment is connected to a hydrocyclone, which is used to separate the inorganic hydroxyapatite core and the sludge containing high organic matter to achieve phosphorus recovery;

[0012] The hydrocyclone is connected to a sludge fermentation tank. The sludge containing high organic matter separated by the hydrocyclone is introduced into the sludge fermentation tank for fermentation. The volatile fatty acids in the sludge fermentation liquid provide a carbon source for the biomineralization / endogenous short-range denitrification reactor, thereby achieving the reduction and resource utilization of excess sludge.

[0013] Furthermore, the municipal wastewater inlet tank is rich in COD, NH4 + -N wastewater, industrial wastewater inlet tank is rich in NO3 - -N、PO4 3- The wastewater in the dosing box contains CaCl2 solution.

[0014] Furthermore, in the anaerobic zone of the biomineralization / endogenous short-cut denitrification reactor, microorganisms absorb organic matter in urban domestic wastewater and sludge fermentation liquid, convert them into intracellular carbon sources PHAs and release a large amount of phosphorus; in the anoxic zone of the biomineralization / endogenous short-cut denitrification reactor, microorganisms use the PHAs stored in the anaerobic zone to convert NO3 in industrial wastewater into - Converted into NO2 - , and absorb a large amount of phosphorus; the added CaCl2 solution causes biomineralization to occur in the anoxic zone, forming endogenous short-range denitrification granular sludge with hydroxyapatite as the core.

[0015] Furthermore, the supernatant of the effluent from the sedimentation tank is connected to an intermediate water tank, which is connected to the anaerobic ammonium oxidation reactor; when the anaerobic ammonium oxidation reactor is started, the intermediate water tank is used to distribute water to ensure the ratio of ammonia nitrogen to nitrite nitrogen in the influent; when the biomineralization / endogenous short-cut denitrification reactor and the anaerobic ammonium oxidation reactor are operated in series, the intermediate water tank serves as a buffer tank to ensure the stable operation of the system.

[0016] Furthermore, when the system is in stable operation, urban domestic wastewater, sludge fermentation liquid and industrial wastewater are added as total influent in a certain proportion to the biomineralization / endogenous short-cut denitrification reactor, and the endogenous denitrification is controlled at NO2 - -N stage, achieving NO2 - -N enrichment, the hydraulic retention time of urban domestic wastewater is 1.5 to 3 hours, and the hydraulic retention time of industrial wastewater is 1 to 3 hours; 2+ and total influent PO4 3- The CaCl2 solution is added at a molar concentration ratio of 2 to 5:1; the sludge return pump at the bottom of the sedimentation tank controls the sludge return ratio to 50 to 150%, and controls the sludge concentration in the biomineralization / endogenous short-cut denitrification reactor to 2000 to 5000 mg / L.

[0017] Furthermore, after the biomineralization / endogenous short-cut denitrification reactor is in stable operation, the COD / NO3 in the total influent is controlled. - -N is 3.2~3.5:1.

[0018] Furthermore, the NO2 in the intermediate water tank - -N and NH4 + -N ratio is controlled at 1.0~1.5:1.

[0019] Furthermore, in the anaerobic ammonium oxidation reactor, the filler filling ratio is 10-20%, the sludge concentration in the anaerobic ammonium oxidation reactor is controlled at 3000-5000 mg / L, excess sludge is discharged from the side outlet of the anaerobic ammonium oxidation reactor in a timely manner, the hydraulic retention time in the anaerobic ammonium oxidation reactor is 2-8 hours, and the wastewater reflux pump controls the wastewater reflux ratio to 100-500%.

[0020] Furthermore, the sedimentation tank regularly discharges sludge into the sludge ultrasonic dispersion equipment at a frequency of 1 day / time. The granular sludge from the sedimentation tank is ultrasonically dispersed in the sludge ultrasonic dispersion equipment. The frequency of the ultrasonic wave is 20 to 28 kHz, the power is 65 W, and the action time is 5 to 10 minutes. The sludge after ultrasonic treatment is transported to the hydrocyclone.

[0021] Furthermore, the fermentation temperature in the sludge fermentation tank is 30-45° C., the fermentation time is 5-10 days, the COD content in the sludge fermentation liquid is 500-1000 mg / L, and the influent ratio of urban domestic wastewater to sludge fermentation liquid is 4-9:1.

[0022] Beneficial effects of the present invention:

[0023] 1. While removing nitrogen, phosphorus and organic pollutants from wastewater, it also realizes the resource recovery of phosphorus;

[0024] 2. The combination of endogenous short-cut denitrification and biomineralization phosphorus removal improves the phosphorus removal rate and phosphorus recovery rate of the wastewater treatment system;

[0025] 3. The short doubling time of heterotrophic denitrifying microorganisms allows the discharge of granular sludge from the reactor to achieve continuous phosphorus removal and phosphorus recovery, and to provide stable NO2 for anaerobic ammonium oxidation in a sustainable and efficient manner. - supply;

[0026] 4. The separate operation of biomineralization phosphorus removal and anaerobic ammonium oxidation denitrification reaction allows the recovery of phosphorus from sludge without adversely affecting anaerobic ammonium oxidation, thus ensuring the stable operation of the anaerobic ammonium oxidation reactor;

[0027] 5. The use of ultrasonic dispersion equipment and cyclones is conducive to the efficient separation of hydroxyapatite cores and high organic matter sludge in granular sludge;

[0028] 6. The inorganic core separated from the granular sludge is mainly composed of hydroxyapatite, which is conducive to the efficient recovery of phosphorus;

[0029] 7. The sludge containing a large amount of organic matter separated from the granular sludge can produce volatile fatty acids through sludge fermentation to provide a carbon source for denitrification, thereby achieving the reduction and resource utilization of the remaining sludge. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The present invention relates to a schematic structural flow chart of a wastewater treatment system.

[0031] The names corresponding to the marks in the figure are:

[0032] 1. Municipal wastewater inlet tank; 1.1. Transfer pump A; 2. Industrial wastewater inlet tank; 2.1. Transfer pump B; 3. Dosing tank; 3.1. Transfer pump C; 4. Biomineralization / endogenous short-range denitrification reactor; 4.1. Anaerobic zone; 4.2. Anoxic zone; 4.3. Agitation device A; 5. Sedimentation tank; 5.1. Sludge return pump; 5.2. Sludge pump; 6. Intermediate water tank; 6.1. Transfer pump D; 7. Anaerobic ammonium oxidation Reactor; 7.1. Drain outlet; 7.2. Wastewater reflux pump; 7.3. Filler; 8. Sludge ultrasonic dispersion equipment; 8.1. Ultrasonic vibrating rod; 9. Hydrocyclone; 9.1. Feed inlet A; 9.2. Top outlet; 9.3. Bottom outlet; 10. Sludge fermentation tank; 10.1. Feed inlet B; 10.2. Discharge outlet; 10.3. Exhaust outlet; 10.4. Agitation device B; 10.5. Delivery pump E. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0034] The principle of the present invention is:

[0035] Municipal domestic wastewater, sludge fermentation liquid and return sludge from sedimentation tank 5 enter the anaerobic zone 4.1 of biomineralization / endogenous short-cut denitrification reactor 4. In the anaerobic zone 4.1, microorganisms absorb organic matter in municipal domestic wastewater and sludge fermentation liquid and convert them into intracellular carbon source PHAs and release a large amount of phosphorus. In the anoxic zone 4.2, microorganisms use PHAs stored in the anaerobic stage to convert NO3 in industrial wastewater into - Converted into NO2 - , and absorb a large amount of phosphorus; in addition, CaCl2 is added to the biomineralization / endogenous short-cut denitrification reactor 4 through the dosing box 3 to form an endogenous short-cut denitrification granular sludge with hydroxyapatite as the core, while strengthening the removal of phosphorus in the wastewater.

[0036] The mud-water mixture from the biomineralization / endogenous short-range denitrification reactor 4 enters the sedimentation tank 5 for mud-water separation. After separation, the mixture contains NO2 - and NH4 + The supernatant enters the intermediate water tank 6 and then enters the anaerobic ammonium oxidation reactor 7 to achieve efficient removal of nitrogen in the wastewater, ultimately ensuring that the wastewater meets discharge standards.

[0037] After separation in sedimentation tank 5, a portion of the granular sludge is returned to anaerobic zone 4.1 of biomineralization / endogenous short-cut denitrification reactor 4 to maintain an appropriate sludge concentration. Another portion of the granular sludge passes through an ultrasonic dispersion device and a hydrocyclone 9 to separate the inorganic hydroxyapatite core from the high-organic matter sludge. The separated inorganic hydroxyapatite core, after further purification, can be directly used as fertilizer in agricultural fields or as an adsorbent for removing dyes, emerging pollutants, and heavy metals, facilitating phosphorus recovery and resource utilization. The separated high-organic matter sludge is fermented in a sludge fermentation tank 10 to produce volatile fatty acids, which provide a carbon source for biomineralization / endogenous short-cut denitrification reactor 4. The wastewater treatment system of the present invention achieves simultaneous, low-carbon, high-efficiency denitrification and phosphorus removal, phosphorus resource recovery, and excess sludge reduction and resource utilization, significantly impacting environmental protection and resource recovery.

[0038] Example 1

[0039] like Figure 1 As shown, in this embodiment, a biomineralization / endogenous short-cut denitrification reactor 4 is provided. The biomineralization / endogenous short-cut denitrification reactor 4 includes an anaerobic zone 4.1 and an anoxic zone 4.2. There are two anaerobic zones 4.1 and two anoxic zones 4.2, and a stirring device A4.3 is provided in each anaerobic zone 4.1 and anoxic zone 4.2.

[0040] The municipal wastewater inlet tank 1 is connected to the anaerobic zone 4.1 of the biomineralization / endogenous short-cut denitrification reactor 4 through a delivery pump A1.1, the industrial wastewater inlet tank 2 is connected to the anoxic zone 4.2 of the biomineralization / endogenous short-cut denitrification reactor 4 through a delivery pump B2.1, and the dosing tank 3 is connected to the anoxic zone 4.2 of the biomineralization / endogenous short-cut denitrification reactor 4 through a delivery pump C3.1.

[0041] The effluent from the biomineralization / endogenous short-cut denitrification reactor 4 is connected to the sedimentation tank 5, which is connected to the intermediate water tank 6. The intermediate water tank 6 is connected to the anaerobic ammonium oxidation reactor 7 via a delivery pump D6.1. The anaerobic ammonium oxidation reactor 7 is filled with polyethylene filler 7.3. A return pipe is provided between the bottom and the top of the anaerobic ammonium oxidation reactor 7. A wastewater return pump 7.2 is installed on the return pipe. The sewage returns from the top to the bottom of the anaerobic ammonium oxidation reactor 7. A drain outlet 7.1 is provided above the anaerobic ammonium oxidation reactor 7, and the sludge return point is located below the drain outlet 7.1.

[0042] Part of the granular sludge discharged from the bottom of the sedimentation tank 5 is returned to the anaerobic zone 4.1 of the biomineralization / endogenous short-range denitrification reactor 4 through a pipeline, and the other part is transported to the sludge ultrasonic dispersion device 8 through a sludge pump 5.2. An ultrasonic vibration rod 8.1 is installed in the sludge ultrasonic dispersion device 8. The discharge of the sludge ultrasonic dispersion device 8 is connected to the feed port A9.1 of the hydrocyclone 9. A top outlet 9.2 is provided above the hydrocyclone 9, and a bottom outlet 9.3 is provided below the hydrocyclone 9. The bottom outlet 9.3 is the outlet for the granular sludge core, and the top outlet 9.2 is the outlet for the sludge containing high organic matter content.

[0043] Sludge containing high organic matter content enters the sludge fermentation tank 10 through the feed port B10.1. A stirring device B10.4 is provided in the sludge fermentation tank 10. An exhaust port 10.3 is provided above the sludge fermentation tank 10, and a discharge port 10.2 is provided at the bottom of the sludge fermentation tank 10. The sludge fermentation liquid produced by the fermentation in the sludge fermentation tank 10 is discharged through the discharge port 10.2 and transported to the anaerobic zone 4.1 of the biomineralization / endogenous short-range denitrification reactor 4 through the delivery pump E10.5.

[0044] Based on the wastewater treatment system of this embodiment, the treatment process of urban domestic wastewater and industrial wastewater in this system is described in detail below.

[0045] In this embodiment, the specific test water is simulated urban domestic wastewater and industrial wastewater. The water quality of urban domestic wastewater is as follows: COD concentration is 400 mg / L, NH4 + -N concentration is 50mg / L, NO2 - -N≤0.5mg / L, NO3 - -N≤0.5mg / L, P=6mg / L, CaCl2·2H2O=14mg / L, MgSO4·7H2O=90mg / L. The water quality of industrial wastewater is as follows: NO3 - -N=120mg / L, P=33mg / L.

[0046] Each reactor is made of organic glass, and the effective volume of the biomineralization / endogenous short-cut denitrification reactor 4 is 32L.

[0047] S1. Start-up of biomineralization / endogenous short-cut denitrification reactor 4

[0048] a. The activated sludge from the municipal wastewater treatment plant was added to the biomineralization / endogenous short-cut denitrification reactor 4, so that the sludge concentration in the reactor was MLSS = 3500 mg / L;

[0049] b. Municipal wastewater in the municipal wastewater inlet tank 1 and granular sludge settled in the sedimentation tank 5 enter the anaerobic zone 4.1 of the biomineralization / endogenous short-cut denitrification reactor 4 via a transfer pump A1.1 and a sludge return pump 5.1, respectively. The hydraulic retention time (HRT) is 2 hours and the sludge return ratio is 100%. The industrial wastewater inlet tank 2 enters the anoxic zone 4.2 of the biomineralization / endogenous short-cut denitrification reactor 4 via a transfer pump. The HRT is 1.5 hours. The inflow ratio of municipal wastewater to industrial wastewater is 2:1.

[0050] c. When NO2 is discharged from the water - and NH4 + The mass concentration ratio was maintained at about 1.2 for 25 days, indicating that the biomineralization / endogenous short-cut denitrification reactor 4 was successfully started.

[0051] S2. Startup of anaerobic ammonium oxidation reactor 7

[0052] a. The mature anaerobic ammonium oxidation granular sludge and anaerobic ammonium oxidation biofilm filler 7.3 is directly inoculated into the anaerobic ammonium oxidation reactor 7, so that the sludge concentration in the reactor MLSS = 4000 mg / l, the filling ratio is 15%;

[0053] b. The HRT of the anaerobic ammonium oxidation reactor 7 is 6h, and the reflux ratio of the wastewater reflux pump 7.2B control system is 300%;

[0054] c. Pump the water into the anaerobic ammonium oxidation reactor 7 through the delivery pump D6.1, and preset NH4 + and NO2 - The concentrations are 50 mg / L and 60 mg / L respectively. When the total nitrogen removal rate in the system is higher than 75% and maintained for 30 days, it indicates that the anaerobic ammonium oxidation reactor 7 is successfully started;

[0055] S3, biomineralization / endogenous short-cut denitrification reactor 4 and anaerobic ammonium oxidation reactor 7 series operation

[0056] a. The sludge-water mixture in the biomineralization / endogenous shortcut denitrification reactor 4 is separated into sludge and water in a sedimentation tank 5. The supernatant after separation is discharged into an intermediate water tank 6. The separated granular sludge is pumped into the anaerobic zone 4.1 of the biomineralization / endogenous shortcut denitrification reactor 4 via a sludge return pump 5.1. The sludge return ratio is 100%.

[0057] b. Pump the wastewater from the intermediate water tank 6 into the anaerobic ammonium oxidation reactor 7 via transfer pump D6.1, with an HRT of 6 hours and a reflux ratio of 300%. When the total nitrogen removal rate in the system exceeds 80% and is maintained for 25 days, the biomineralization / endogenous short-cut denitrification reactor 4 and the anaerobic ammonium oxidation reactor 7 are successfully connected in series.

[0058] S4. Operation of the biomineralization / endogenous short-cut denitrification combined with anaerobic ammonium oxidation system for simultaneous nitrogen and phosphorus removal and phosphorus recovery

[0059] a. After the biomineralization / endogenous short-cut denitrification reactor 4 and the anaerobic ammonium oxidation reactor 7 are successfully connected in series, CaCl2 is pumped from the dosing tank 3 to the anoxic zone 4.2 of the biomineralization / endogenous short-cut denitrification reactor 4 through the delivery pump C3.1 to control the total influent Ca 2+ and PO4 3- The molar concentration ratio is 3:1;

[0060] b. After sedimentation in the sedimentation tank 5, part of the sludge is returned to the anaerobic zone 4.1 of the biomineralization / endogenous short-range denitrification reactor 4 through the sludge return pump 5.1, and the other part of the sludge is regularly discharged to the sludge ultrasonic dispersion equipment 8 through the sludge pump 5.2;

[0061] c. After the granular sludge is dispersed by an ultrasonic dispersing device, it is pumped into the hydrocyclone 9 through the feed port B10.1. In the hydrocyclone 9, centrifugal force is used to separate the hydroxyapatite core and the high-organic matter sludge in the granular sludge;

[0062] d. The hydroxyapatite core separated by the hydrocyclone 9 is discharged from the discharge pipe, and the hydroxyapatite core is further purified to achieve resource recovery and utilization of phosphorus;

[0063] e. The separated high organic matter sludge is discharged from the discharge pipe and then enters the sludge fermentation tank 10 for fermentation. The sludge fermentation liquid is fed into the anaerobic zone 4.1 of the biomineralization / endogenous short-cut denitrification reactor 4 through the delivery pump E10.5 together with the urban domestic wastewater in the urban wastewater inlet tank 1 and the sludge returned from the sedimentation tank 5. The inflow of urban domestic wastewater is appropriately reduced so that the COD / NO3 in the total inflow is - -N is 3.2~3.5:1, and NO2 in the middle water tank - -N and NH4 + -N ratio is controlled at 1.0~1.5:1.

[0064] The test results show that after stable operation, the final effluent COD of the reactor is 30-50 mg / L, NH4 + -N<3mg / L, NO2 - -N<1mg / L, NO3 - -N<3mg / L, P<0.5mg / L, the average total nitrogen removal rate can reach more than 90%, the average phosphorus removal rate can reach more than 95%, and the phosphorus recovery rate is 40-60%.

[0065] The device and method for biomineralization-induced hydroxyapatite formation, enhanced endogenous short-range denitrification, simultaneous denitrification and phosphorus removal and phosphorus recovery can be widely used in the treatment of urban domestic wastewater and other phosphorus-containing industrial wastewater and phosphorus recovery.

[0066] The present invention is not limited to the above-mentioned optimal implementation mode. Anyone can derive other forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, any technical solution that is the same or similar to that of the present application falls within the scope of protection of the present invention.

Claims

1. Biomineralization / endogenous short-range denitrification coupled anaerobic ammonium oxidation wastewater treatment system, characterized by: It includes a biomineralization / endogenous short-range denitrification reactor (4), an anaerobic ammonium oxidation reactor (7), a sludge ultrasonic dispersion device (8), a hydrocyclone (9) and a sludge fermentation tank (10); The biomineralization / endogenous short-cut denitrification reactor (4) includes an anaerobic zone (4.1) and an anoxic zone (4.2). The anaerobic zone (4.1) is connected to the municipal wastewater inlet tank (1), and the anoxic zone (4.2) is connected to the industrial wastewater inlet tank (2) and the dosing box (3). A chemical is added to the anoxic zone (4.2) via the dosing box (3), thereby inducing biomineralization in the anoxic zone (4.2) and forming an endogenous short-cut denitrification granular sludge with hydroxyapatite as the core, thereby achieving phosphorus removal. The municipal wastewater inlet tank (1) is rich in COD and NH4 + -N domestic wastewater, industrial wastewater inlet tank is rich in NO3 - -N、PO4 3- The wastewater in the dosing box (3) contains CaCl2 solution; The effluent from the anoxic zone (4.2) is connected to the sedimentation tank (5), and the supernatant from the effluent from the sedimentation tank (5) is introduced into the anaerobic ammonium oxidation reactor (7), where an anaerobic ammonium oxidation reaction occurs to achieve simultaneous removal of ammonia nitrogen and nitrite nitrogen; a portion of the granular sludge precipitated from the sedimentation tank (5) is returned to the anaerobic zone (4.1) of the biomineralization / endogenous short-range denitrification reactor (4) to maintain an appropriate sludge concentration, and the other portion is introduced into the sludge ultrasonic dispersion equipment (8); The sludge ultrasonic dispersion device (8) is provided with an ultrasonic vibration rod (8.1), and the sludge ultrasonic dispersion device (8) is used to disperse the inorganic hydroxyapatite core in the granular sludge and the sludge containing high organic matter; The sludge ultrasonic dispersion device (8) is connected to a hydrocyclone (9), which is used to separate the inorganic hydroxyapatite core and the sludge containing high organic matter, thereby realizing phosphorus recovery; The hydrocyclone (9) is connected to the sludge fermentation tank (10). The sludge containing high organic matter separated by the hydrocyclone (9) is introduced into the sludge fermentation tank (10) for fermentation. The volatile fatty acids in the sludge fermentation liquid provide a carbon source for the biomineralization / endogenous short-range denitrification reactor (4), thereby achieving the reduction and resource utilization of excess sludge.

2. The biomineralization / endogenous short-cut denitrification coupled anaerobic ammonium oxidation wastewater treatment system according to claim 1, characterized in that: In the anaerobic zone (4.1) of the biomineralization / endogenous short-cut denitrification reactor (4), microorganisms absorb organic matter in domestic wastewater and sludge fermentation liquid, convert them into intracellular carbon sources PHAs and release a large amount of phosphorus; in the anoxic zone (4.2) of the biomineralization / endogenous short-cut denitrification reactor (4), microorganisms use the PHAs stored in the anaerobic zone (4.1) to convert NO3 in industrial wastewater into - Converted to NO2 - , and absorb a large amount of phosphorus; the added CaCl2 solution causes biomineralization to occur in the anoxic zone (4.2), forming endogenous short-range denitrification granular sludge with hydroxyapatite as the core.

3. The biomineralization / endogenous short-cut denitrification coupled anaerobic ammonium oxidation wastewater treatment system according to claim 1, characterized in that: The supernatant of the effluent from the sedimentation tank (5) is connected to the intermediate water tank (6), which is connected to the anaerobic ammonium oxidation reactor (7); when the anaerobic ammonium oxidation reactor (7) is started, the intermediate water tank (6) is used to distribute water to ensure the ratio of ammonia nitrogen to nitrite nitrogen in the influent; when the biomineralization / endogenous short-cut denitrification reactor (4) and the anaerobic ammonium oxidation reactor (7) are operated in series, the intermediate water tank (6) serves as a buffer tank to ensure the stable operation of the system.

4. The biomineralization / endogenous short-cut denitrification coupled anaerobic ammonium oxidation wastewater treatment system according to claim 1, characterized in that: When the system is in stable operation, domestic wastewater, sludge fermentation liquid and industrial wastewater are added as total influent in a certain proportion into the biomineralization / endogenous short-range denitrification reactor (4), and the endogenous denitrification is controlled at NO2 - -N stage, achieving NO2 - -N enrichment, the hydraulic retention time of domestic wastewater is 1.5~3h, and the hydraulic retention time of industrial wastewater is 1~3h; 2+ and total influent PO4 3- The CaCl2 solution is added at a molar concentration ratio of 2 to 5:1; the sludge return pump (5.1) at the bottom of the sedimentation tank (5) controls the sludge return ratio to 50 to 150%, and controls the sludge concentration in the biomineralization / endogenous short-cut denitrification reactor (4) to 2000 to 5000 mg / L.

5. The biomineralization / endogenous short-cut denitrification coupled anaerobic ammonium oxidation wastewater treatment system according to claim 4, characterized in that: After the biomineralization / endogenous short-cut denitrification reactor (4) is in stable operation, the COD / NO3 in the total influent is controlled. - -N is 3.2~3.5:

1.

6. The biomineralization / endogenous short-cut denitrification coupled anaerobic ammonium oxidation wastewater treatment system according to claim 3, characterized in that: The NO2 in the intermediate water tank (6) - -N and NH4 + -N ratio is controlled at 1.0~1.5:

1.

7. The biomineralization / endogenous short-cut denitrification coupled anaerobic ammonium oxidation wastewater treatment system according to claim 6, characterized in that: In the anaerobic ammonium oxidation reactor (7), the filling ratio of the filler (7.3) is 10-20%, the sludge concentration in the anaerobic ammonium oxidation reactor (7) is controlled to be 3000-5000 mg / L, the excess sludge is discharged in time from the side outlet of the anaerobic ammonium oxidation reactor (7), and the hydraulic retention time in the anaerobic ammonium oxidation reactor (7) is 2-8 hours; a return pipe is provided between the bottom and the top of the anaerobic ammonium oxidation reactor (7), and a wastewater return pump (7.2) is installed on the return pipe. The wastewater return direction is from the top to the bottom of the anaerobic ammonium oxidation reactor (7), and the wastewater return pump (7.2) controls the wastewater return ratio to be 100-500%.

8. The biomineralization / endogenous short-cut denitrification coupled anaerobic ammonium oxidation wastewater treatment system according to claim 1, characterized in that: The sedimentation tank (5) is regularly discharged into the sludge ultrasonic dispersion device (8), with a discharge frequency of once a day. The granular sludge from the sedimentation tank (5) is subjected to ultrasonic dispersion treatment in the sludge ultrasonic dispersion device (8). The frequency of the ultrasonic wave is 20-28 kHz, the power is 65 W, and the action time is 5-10 minutes. After the ultrasonic treatment, the sludge is transported to the hydrocyclone (9).

9. The biomineralization / endogenous short-cut denitrification coupled anaerobic ammonium oxidation wastewater treatment system according to claim 5, characterized in that: The fermentation temperature in the sludge fermentation tank (10) is 30-45°C, the fermentation time is 5-10 days, the COD content in the sludge fermentation liquid is 500-1000 mg / L, and the influent ratio of domestic wastewater to sludge fermentation liquid is 4-9:1.

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