A system and method for enhancing the operation of a PD / A granulation process under heavy metal stress based on HAPs

Abstract

The application discloses a kind of based on HAP reinforcing heavy metal stress under PD / A particle process operating system and method, including raw water tank, raw water tank is connected with short-path denitrification reactor, short-path denitrification reactor is connected with first intermediate water tank, first intermediate water tank is connected with first anaerobic ammonia oxidation reactor, first anaerobic ammonia oxidation reactor is connected with second intermediate water tank, second intermediate water tank is connected with short-path denitrification-hydroxyapatite coupling reactor, short-path denitrification-hydroxyapatite coupling reactor is connected with third intermediate water tank, third intermediate water tank is connected with second anaerobic ammonia oxidation reactor, short-path denitrification reactor and short-path denitrification-hydroxyapatite coupling reactor are connected with hydrocyclone respectively.The application utilizes hydroxyapatite circulation to cooperate sludge sorting reuse, effectively alleviate the inhibition of heavy metal to anaerobic ammonia oxidation system, improve the operation stability of PD / A system under the stress of reinforcing heavy metal.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, and in particular relates to a PD / A particle process operation system and method based on HAP-enhanced heavy metal stress. Background Technology

[0002] Industrial wastewater is complex in composition, typically containing high concentrations of nitrogen, phosphorus, and various heavy metal pollutants. Traditional biological nitrogen removal processes suffer from problems such as high carbon source requirements, high energy consumption, and large sludge production, making it difficult to meet the requirements of low-carbon and high-efficiency treatment. Partial denitrification / anammox (PD / A) technology is considered a highly promising biological nitrogen removal process due to its advantages such as no need for external carbon sources, low energy consumption, and low sludge production. However, anammox bacteria (AnAOB) are extremely sensitive to environmental stresses, especially heavy metal ions, which can significantly reduce their activity or even cause inactivation, severely limiting the widespread application of PD / A technology in the treatment of industrial wastewater containing heavy metals.

[0003] Recent studies have shown that the coupling of hydroxyapatite (HAP) within granular sludge can significantly improve its settling performance. Simultaneously, HAP, acting as the framework of granular sludge, enhances its mechanical strength, thereby strengthening the system's biological retention capacity and ensuring its long-term stable operation. Furthermore, as an excellent adsorbent, the Ca²⁺ in HAP's crystal lattice can undergo ion exchange with heavy metal ions such as Cu²⁺ and Ni²⁺, and its surface functional groups can efficiently capture heavy metal ions through coordination complexation.

[0004] Therefore, this invention proposes a PD / A particle process operation system and method based on HAP-enhanced heavy metal stress, providing a feasible solution for the stable application of PD / A technology in industrial wastewater containing heavy metals. Summary of the Invention

[0005] The purpose of this invention is to provide a process operation system and method for PD / A particles under heavy metal stress based on HAP enhancement, so as to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the present invention provides the following solution: The present invention provides a PD / A particle process operation system based on HAP enhanced heavy metal stress, including a raw water tank, the raw water tank being connected to a short-cut denitrification reactor, the short-cut denitrification reactor being connected to a first intermediate water tank, the first intermediate water tank being connected to a first anammox reactor, the first anammox reactor being connected to a second intermediate water tank, the second intermediate water tank being connected to a short-cut denitrification-hydroxyapatite coupled reactor, the short-cut denitrification-hydroxyapatite coupled reactor being connected to a third intermediate water tank, the third intermediate water tank being connected to a second anammox reactor, and the short-cut denitrification reactor and the short-cut denitrification-hydroxyapatite coupled reactor being respectively connected to hydrocyclones.

[0007] Optionally, the short-cut denitrification reactor includes a first stirrer disposed within the short-cut denitrification reactor, the raw water tank is connected to the first inlet of the short-cut denitrification reactor via a first inlet pump, and the first outlet of the short-cut denitrification reactor is connected to the first intermediate water tank.

[0008] Optionally, the bottom of the short-cut denitrification reactor is provided with a first sludge inlet, which is connected to the hydrocyclone via a first sludge pump.

[0009] Optionally, the bottom of the first anaerobic ammonia oxidation reactor is provided with a second water inlet, which is connected to a second water inlet pump and a first reflux pump. The second water inlet pump is connected to the first intermediate water tank, and the first reflux pump is connected to a first reflux port. The first reflux port is connected to the top of the first anaerobic ammonia oxidation reactor. The top of the first anaerobic ammonia oxidation reactor is also provided with a second drain outlet, which is connected to the second intermediate water tank and is located above the first reflux port.

[0010] Optionally, the short-cut denitrification-hydroxyapatite coupled reactor is equipped with a second stirrer. The top of the short-cut denitrification-hydroxyapatite coupled reactor is connected to a carbon source storage tank and a calcium source storage tank, respectively. The short-cut denitrification-hydroxyapatite coupled reactor is provided with a third water inlet on the side near the second intermediate water tank. The third water inlet is connected to the second intermediate water tank through a third water pump. The side of the short-cut denitrification-hydroxyapatite coupled reactor away from the second intermediate water tank is connected to the third intermediate water tank through a third drain outlet. The short-cut denitrification-hydroxyapatite coupled reactor is connected to the hydrocyclone through a first sludge discharge outlet and a second sludge inlet.

[0011] Optionally, the short-cut denitrification-hydroxyapatite coupled reactor is connected to the carbon source storage tank via a fourth inlet and a fourth inlet pump, and the short-cut denitrification-hydroxyapatite coupled reactor is connected to the calcium source storage tank via a fifth inlet pump and a fifth inlet.

[0012] Optionally, a first sludge discharge pump is connected between the first sludge discharge port and the hydrocyclone, and a second sludge inlet pump is connected between the second sludge inlet and the hydrocyclone.

[0013] Optionally, the bottom of the second anaerobic ammonia oxidation reactor is provided with a sixth water inlet, which is connected to the third intermediate water tank through a sixth water inlet pump. The sixth water inlet is connected to a second reflux port through a second reflux pump. The second reflux port is located at the top of the second anaerobic ammonia oxidation reactor. A fourth drain port is provided above the second reflux port, which is connected to an outlet tank.

[0014] Optionally, the raw water tank contains substances containing heavy metals and NO3. - -N industrial wastewater and NH4-containing + -N industrial wastewater.

[0015] An operation method for a PD / A particle process operating system based on HAP-enhanced heavy metal stress includes the following steps: S1, containing heavy metals and NO3 - -N industrial wastewater and NH4-containing + -N industrial wastewater is pumped into the raw water tank, where the pH is adjusted to maintain the wastewater's pH at 6.5-8.0. - -N / NH4 + The -N mass concentration ratio is 1.0-2.0, and the COD and NO3 concentrations are... - The ratio of -N mass concentration is less than 3.0, and the ratio of total nitrogen to dissolved phosphorus mass concentration is less than 20.0; S2. Pump the mixed wastewater from the raw water tank into the short-cut denitrification reactor. The sludge concentration is 10.0-16.0 g / L, and the sludge retention time is 8-15 days. S3. Pump the effluent from the short-cut denitrification reactor into the first anaerobic ammonia oxidation reactor. Control the sludge concentration in the first anaerobic ammonia oxidation reactor to be 5.0-20.0 g / L during operation. The effluent NO2... - -N concentration less than 5.0 mg / L; S4. The effluent from the first anaerobic ammonia oxidation reactor and the carbon source are pumped together into the short-cut denitrification-hydroxyapatite coupled reactor to control COD and NO3 levels within the reactor. -The NO3-N mass concentration ratio is 2.0-4.0. The Ca / P mass concentration ratio in the short-cut denitrification-hydroxyapatite coupled reactor is adjusted to 2.0-5.0 using calcium chloride and calcium hydroxide. The sludge concentration in the short-cut denitrification-hydroxyapatite coupled reactor is controlled at 15.0-25.0 g / L, and the sludge retention time is 5-10 days. The effluent NO3... - -N concentration less than 10.0 mg / L; S5. Pump the effluent from the short-cut denitrification-hydroxyapatite coupled reactor into the second anaerobic ammonium oxidation reactor. Control the sludge concentration (MLSS) of the second anaerobic ammonium oxidation reactor to be 10.0-20.0 g / L during operation. The effluent NH4+... + -N concentration less than 3.0 mg / L, NO3 - -N concentration less than 5.0 mg / L; In S2, 1.5-4.0 g / L of short-cut denitrification-hydroxyapatite coupled granular sludge is pumped into the short-cut denitrification reactor daily; In S3, NO2 is emitted from the water. - When the NO2 concentration is greater than 5.0 mg / L, extend the sludge retention time in the first anaerobic ammonia oxidation reactor until the effluent NO2 - -N concentration less than 5.0 mg / L; In S4, NO3 is emitted. - When the -N concentration is greater than 10.0 mg / L, it increases COD and NO3. - -N mass concentration ratio until NO3 in the effluent - -N concentration less than 10.0 mg / L; In S4, 15-40% of the sludge is discharged into the hydrocyclone, the sludge at the bottom of the hydrocyclone is pumped into the short-cut denitrification reactor, and the sludge at the top is returned to the short-cut denitrification-hydroxyapatite coupled reactor. In S5, NH4 + When the NO3- concentration is greater than 3.0 mg / L, the NO3- concentration in the mixed influent of the short-cut denitrification reactor will increase. - -N and NH4 + -N mass concentration ratio until NH4 in the effluent of the second anaerobic ammonia oxidation reactor. + -N concentration less than 3.0 mg / L; NO3 - When the NO3- concentration is greater than 5.0 mg / L, extend the hydraulic retention time of the second anaerobic ammonia oxidation reactor until the effluent NO3- - -N concentration less than 5.0 mg / L; NH4 + -N concentration greater than 3.0 mg / L and NO3 - When the -N concentration is greater than 5.0 mg / L, the COD and NO3 levels in the short-path denitrification-hydroxyapatite coupled reactor increase. --N mass concentration ratio until NH4 in the effluent + -N concentration less than 3.0 mg / L and NO3 - -N concentration less than 5.0 mg / L.

[0016] This invention discloses the following technical effects: It utilizes hydroxyapatite recycling in conjunction with sludge sorting and reuse to effectively alleviate the inhibitory effect of heavy metals on anaerobic ammonium oxidation systems and improve the operational stability of the PD / A system under enhanced heavy metal stress. A post-short-cut denitrification-hydroxyapatite coupled reactor in a low-metal environment efficiently produces hydroxyapatite, avoiding heavy metal interference in the hydroxyapatite production process and ensuring a continuous and stable supply of hydroxyapatite. Sludge is reused in stages using a hydrocyclone; low-inorganic-component sludge is returned to maintain biomass, while high-inorganic-component sludge (rich in hydroxyapatite) is reused for heavy metal adsorption, improving hydroxyapatite recycling efficiency and reducing external addition and operating costs. The high-inorganic-component sludge entering the short-cut denitrification reactor can serve as an effective biomass supplement to the system under enhanced heavy metal stress, achieving synergistic sludge efficiency and further enhancing the robustness of the PD / A system under heavy metal shocks. Hydroxyapatite is synthesized in a post-reactor unit and added as needed, avoiding the damage to the particle structure caused by disordered deposition of hydroxyapatite in the pre-reactor and reducing the operational risk of the system under enhanced heavy metal stress. The short doubling time of short-range denitrifying bacteria allows the reactor to discharge large amounts of particles to achieve continuous recycling of hydroxyapatite, while ensuring stable enrichment of nitrite in the system and continuously supplying substrate for the anaerobic ammonium oxidation process. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The embodiments of this application and their descriptions are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the operating system of the PD / A particle process under HAP-enhanced heavy metal stress according to the present invention; Figure 2 This is a process flow diagram of the present invention.

[0018] Figure label: 1. Raw water tank; 2. Short-cut denitrification reactor; 3. First intermediate water tank; 4. First anaerobic ammonium oxidation reactor; 5. Second intermediate water tank; 6. Short-cut denitrification-hydroxyapatite coupled reactor; 7. Hydrocyclone; 8. Third intermediate water tank; 9. Second anaerobic ammonium oxidation reactor; 21. First agitator; 22. First inlet pump; 23. First inlet; 24. First outlet; 25. First sludge pump; 26. First sludge inlet; 41. Second inlet pump; 42. Second inlet; 43. First reflux outlet; 44. First reflux pump ; 45. Second drain outlet; 61. Second agitator; 62. Third water inlet pump; 63. Third water inlet; 64. Carbon source storage tank; 65. Fourth water inlet pump; 66. Fourth water inlet; 67. Calcium source storage tank; 68. Fifth water inlet pump; 69. Fifth water inlet; 610. Third drain outlet; 611. First sludge discharge outlet; 612. First sludge discharge pump; 614. Second sludge pump; 615. Second sludge inlet; 91. Sixth water inlet pump; 92. Sixth water inlet; 93. Second reflux outlet; 94. Second reflux pump; 95. Fourth drain outlet. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] Reference Figures 1 to 2 As shown, this embodiment provides a PD / A granular sludge process operation system based on the HAP (Hydrogen Acid Pore Reduction) cycle enhancement mechanism, specifically designed to address heavy metal stress environments. The system's overall structure includes a raw water tank 1, which is connected to a short-cut denitrification reactor 2 via a pipeline. The effluent from the short-cut denitrification reactor 2 is further connected to a first intermediate water tank 3. The first intermediate water tank 3 is connected to a first anammox reactor 4. The effluent from the first anammox reactor 4 is connected to a second intermediate water tank 5. The second intermediate water tank 5 then directs the water flow into a short-cut denitrification-hydroxyapatite coupled reactor 6. The effluent from this coupled reactor is connected to a third intermediate water tank 8. The third intermediate water tank 8 is subsequently connected to a second anammox reactor 9. Furthermore, the short-cut denitrification reactor 2 and the short-cut denitrification-hydroxyapatite coupled reactor 6 are each independently connected to a hydrocyclone 7 for efficient sorting and treatment of the sludge generated during the reaction process.

[0022] Industrial wastewater flows sequentially through short-cut denitrification reactor 2 and the first anaerobic ammonia oxidation reactor 4. Short-cut denitrification reactor 2 reduces some of the NO3⁻-N to NO2. — The first anaerobic ammonium oxidation reactor 4 removes some nitrogen from the effluent of the short-cut denitrification reactor 2. The effluent from the first anaerobic ammonium oxidation reactor 4, containing excess NO3⁻-N and NH4⁺-N, along with carbon and calcium sources, sequentially enters the short-cut denitrification-hydroxyapatite coupled reactor 6 and the second anaerobic ammonium oxidation reactor 9 to further remove nitrogen from the effluent and stably generate hydroxyapatite. A hydrocyclone 7 is used to achieve the fractional reuse of hydroxyapatite-coupled sludge within the short-cut denitrification-hydroxyapatite coupled reactor 6, significantly improving the recycling efficiency of hydroxyapatite and ensuring a continuous and stable supply of hydroxyapatite and effective removal of heavy metals within the short-cut denitrification system. This invention, by constructing a hydroxyapatite recycling pathway and combining it with the hydrocyclone 7 to achieve precise sludge sorting and directional reuse, significantly improves the overall operational stability, shock load resistance, and synergistic removal efficiency of nitrogen and heavy metal pollutants in the PD / A granular sludge process under heavy metal stress conditions.

[0023] This invention utilizes hydroxyapatite recycling in conjunction with sludge sorting and reuse to effectively alleviate the inhibitory effect of heavy metals on anaerobic ammonium oxidation systems and improve the operational stability of the PD / A system under enhanced heavy metal stress. A post-short-cut denitrification-hydroxyapatite coupled reactor 6, operating in a low-metal environment, efficiently produces hydroxyapatite, avoiding heavy metal interference with the hydroxyapatite production process and ensuring a continuous and stable supply of hydroxyapatite. A hydrocyclone 7 enables the differentiated reuse of sludge: low-inorganic-component sludge is returned to maintain biomass, while high-inorganic-component sludge (rich in hydroxyapatite) is reused for heavy metal adsorption, improving hydroxyapatite recycling efficiency and reducing external additions and operating costs. The high-inorganic-component sludge entering the short-cut denitrification reactor 2 can serve as an effective biomass supplement to the system under enhanced heavy metal stress, achieving synergistic sludge efficiency and further enhancing the robustness of the PD / A system under heavy metal shocks. Hydroxyapatite is synthesized in a post-reactor unit and added as needed, avoiding the damage to the particle structure caused by disordered deposition of hydroxyapatite in the pre-reactor and reducing the operational risk of the system under enhanced heavy metal stress. The short doubling time of short-range denitrifying bacteria allows the reactor to discharge large amounts of particles to achieve continuous recycling of hydroxyapatite, while ensuring stable enrichment of nitrite in the system and continuously supplying substrate for the anaerobic ammonium oxidation process.

[0024] In the further optimized scheme, the short-cut denitrification reactor 2 is equipped with a first stirrer 21 to maintain uniform mixing in the reactor and promote mass transfer efficiency; the raw water tank 1 is stably connected to the first inlet 23 of the short-cut denitrification reactor 2 through the first inlet pump 22, while the first outlet 24 of the short-cut denitrification reactor 2 is directly connected to the first intermediate water tank 3 to ensure smooth water flow.

[0025] In the further optimized scheme, the bottom of the short-cut denitrification reactor 2 is provided with a first sludge inlet 26. This sludge inlet is connected to the high inorganic component outlet of the hydrocyclone 7 through a first sludge pump 25, thereby realizing the directional reflux of hydroxyapatite-rich material to the reactor and enhancing the heavy metal adsorption function.

[0026] In a further optimized design, the bottom of the first anaerobic ammonia oxidation reactor 4 is provided with a second inlet 42, which is connected to the first intermediate water tank 3 via a second inlet pump 41 and connected to the first return port 43 located at the top of the reactor via a first return pump 44, forming an internal circulation to optimize substrate distribution and microbial contact efficiency. The top of the first anaerobic ammonia oxidation reactor 4 is also provided with a second drain port 45, which is located above the first return port 43 and is connected to the second intermediate water tank 5 to ensure that the effluent can smoothly enter the next treatment unit.

[0027] In a further optimized design, the short-cut denitrification-hydroxyapatite coupled reactor 6 is equipped with a second stirrer 61 to ensure thorough mixing of the carbon source, calcium source, and influent, and to promote the nucleation and growth of hydroxyapatite. The reactor top has two independent interfaces, connected to the carbon source storage tank 64 and the calcium source storage tank 67 respectively, for precise addition of exogenous carbon sources (such as sodium acetate) and calcium sources (such as calcium chloride and calcium hydroxide) as needed. A third inlet 63 is located near the second intermediate water tank 5, achieving a stable connection with the second intermediate water tank 5 via a third inlet pump 62. A third outlet 610 is located away from the second intermediate water tank 5, for discharging the treated effluent into the third intermediate water tank 8. Furthermore, the coupled reactor is bidirectionally connected to the hydrocyclone 7 via a first sludge discharge port 611 and a second sludge inlet 615, for sludge discharge and the return of sorted sludge, respectively.

[0028] In the further optimized scheme, the short-cut denitrification-hydroxyapatite coupled reactor 6 is also equipped with a fourth inlet 66, which is connected to the carbon source storage tank 64 through the fourth inlet pump 65 to realize the independent control and addition of carbon source; at the same time, it is connected to the calcium source storage tank 67 through the fifth inlet pump 68 and the fifth inlet 69 to ensure that the calcium ion concentration meets the stoichiometric ratio required for hydroxyapatite generation.

[0029] In the further optimized scheme, a first sludge discharge pump 612 is provided between the first sludge discharge port 611 and the hydrocyclone 7, which is used to efficiently transport the mixed sludge in the coupled reactor to the hydrocyclone; a second sludge inlet pump 614 is provided between the second sludge inlet 615 and the hydrocyclone 7, which is used to return the sorted specific component sludge to the reactor, so as to realize functional control.

[0030] In the further optimized scheme, the bottom of the second anaerobic ammonia oxidation reactor 9 is provided with a sixth inlet 92. This inlet is connected to the third intermediate water tank 8 through the sixth inlet pump 91 to receive the inlet water from the front-end treatment unit. On the other hand, it is connected to the second reflux port 93 located at the top of the reactor through the second reflux pump 94 to form an internal circulation to optimize the reaction conditions. Above the second reflux port 93, there is a fourth drain port 95, which is connected to the final effluent tank to complete the collection of effluent from the entire system.

[0031] In the further optimized scheme, the raw water tank 1 is pre-stored with industrial wastewater to be treated, the components of which include heavy metal ions (such as Cu²⁺, Zn²⁺, Pb²⁺, etc.), nitrate nitrogen (NO3⁻-N) and ammonium nitrogen (NH4⁺-N).

[0032] In the further optimized scheme, the mass concentration ratio of influent COD (chemical oxygen demand) to NO3⁻-N in the short-cut denitrification-hydroxyapatite coupled reactor 6 is strictly controlled between 2.0 and 4.0 to ensure the selectivity and efficiency of the short-cut denitrification process. At the same time, a high sludge concentration is maintained in the reactor, ranging from 15.0 to 25.0 g / L, to ensure sufficient biomass and inorganic nucleation sites, thereby synergistically achieving efficient denitrification and stable hydroxyapatite formation.

[0033] An operation method for a PD / A particle process operating system based on HAP-enhanced heavy metal stress includes the following steps: S1, containing heavy metals and NO3 - -N industrial wastewater and NH4-containing + -N industrial wastewater is pumped into raw water tank 1 to adjust its pH, controlling the pH of the wastewater in raw water tank 1 to be 6.5-8.0, and NO3-. - -N / NH4 + The -N mass concentration ratio is 1.0-2.0, and the COD and NO3 concentrations are... - The ratio of -N mass concentration is less than 3.0, and the ratio of total nitrogen to dissolved phosphorus mass concentration is less than 20.0; S2. Pump the mixed wastewater from raw water tank 1 into short-cut denitrification reactor 2. The sludge concentration is 10.0-16.0 g / L, and the sludge retention time is 8-15 days. S3. Pump the effluent from the short-cut denitrification reactor 2 into the first anaerobic ammonia oxidation reactor 4. Control the sludge concentration of the first anaerobic ammonia oxidation reactor 4 to be 5.0-20.0 g / L during operation, and control the effluent NO2. - -N concentration less than 5.0 mg / L; S4. The effluent from the first anaerobic ammonia oxidation reactor 4, along with the carbon source, is pumped into the short-cut denitrification-hydroxyapatite coupled reactor 6. The carbon source used is sodium acetate, a commonly used commercial carbon source for denitrification. COD and NO3 levels within the short-cut denitrification-hydroxyapatite coupled reactor 6 are controlled. - The NO3-P mass concentration ratio is 2.0-4.0. The Ca / P mass concentration ratio in the short-cut denitrification-hydroxyapatite coupled reactor 6 is adjusted to 2.0-5.0 using calcium chloride and calcium hydroxide. The sludge concentration in the short-cut denitrification-hydroxyapatite coupled reactor 6 is controlled at 15.0-25.0 g / L, the sludge retention time is 5-10 days, and the effluent NO3-P content is controlled. - -N concentration less than 10.0 mg / L; S5. Pump the effluent from the short-cut denitrification-hydroxyapatite coupled reactor 6 into the second anaerobic ammonium oxidation reactor 9. Control the sludge concentration (MLSS) of the second anaerobic ammonium oxidation reactor 9 to be 10.0-20.0 g / L during operation. The effluent NH4... + -N concentration less than 3.0 mg / L, NO3 - -N concentration less than 5.0 mg / L.

[0034] In S2, 1.5-4.0 g / L of short-cut denitrification-hydroxyapatite coupled granular sludge is pumped into the short-cut denitrification reactor 2 daily.

[0035] In S3, NO2 is emitted from the water. - When the NO2 concentration is greater than 5.0 mg / L, extend the sludge retention time of the first anaerobic ammonia oxidation reactor 4 until the effluent NO2 - -N concentration less than 5.0 mg / L.

[0036] In S4, NO3 is emitted. - When the -N concentration is greater than 10.0 mg / L, it increases COD and NO3. - -N mass concentration ratio until NO3 in the effluent - -N concentration less than 10.0 mg / L.

[0037] In S4, 15-40% of the sludge is discharged into hydrocyclone 7, the sludge at the bottom of hydrocyclone 7 is pumped into short-cut denitrification reactor 2, and the sludge at the top is returned to short-cut denitrification-hydroxyapatite coupled reactor 6.

[0038] In S5, NH4 + When the NO3- concentration is greater than 3.0 mg / L, the NO3- concentration in the mixed influent of the short-cut denitrification reactor 2 should be increased. - -N and NH4 + -N mass concentration ratio up to the NH4 in the effluent of the second anaerobic ammonia oxidation reactor 9 + -N concentration less than 3.0 mg / L; NO3 -When the NO3- concentration is greater than 5.0 mg / L, extend the hydraulic retention time of the second anaerobic ammonia oxidation reactor 9 until the effluent NO3- - -N concentration less than 5.0 mg / L; NH4 + -N concentration greater than 3.0 mg / L and NO3 - When the -N concentration is greater than 5.0 mg / L, it increases the COD and NO3 levels in the short-path denitrification-hydroxyapatite coupled reactor 6. - -N mass concentration ratio until NH4 in the effluent + -N concentration less than 3.0 mg / L and NO3 - -N concentration less than 5.0 mg / L.

[0039] Example 1 A system for treating stainless steel pickling wastewater and coking wastewater under heavy metal stress, based on hydroxyapatite-enhanced PD / A process, is proposed. The stainless steel pickling wastewater contains COD: 78.9 mg / L and NO3: 200 mg / L. - -N: 683.3 mg / L, Ni 2 + Phosphorus concentration: 18.9 mg / L, dissolved phosphorus: 180.8 mg / L, pH approximately 2.4; coking wastewater contains NH4+. + -N: 221.6 mg / L, COD: 1000.3 mg / L, pH approximately 7.5.

[0040] Stainless steel pickling wastewater and coking wastewater were pumped into raw water tank 1 at a ratio of 1:2. In raw water tank 1, the wastewater was mixed, homogenized, and the pH was adjusted. NH4 + -N, NO3 - -N, soluble phosphorus, Ni 2+ The concentrations of COD were 151.6 mg / L, 227.3 mg / L, 62.3 mg / L, 6.5 mg / L and 630.4 mg / L, respectively, and the pH was 7.0.

[0041] Mixed wastewater is pumped into short-cut denitrification reactor 2, where the sludge concentration is 12.0 g / L. 3.0 g / L of short-cut denitrification-hydroxyapatite coupled granular sludge is pumped into reactor 2 daily, with a sludge retention time of 10 days. The effluent contains NH4+. + -N, NO3 - -N and NO2 - -N concentrations were 147.9 mg / L, 176.3 mg / L, and 44.2 mg / L.

[0042] The effluent from the short-cut denitrification reactor 2 is pumped into the first anaerobic ammonia oxidation reactor 4. The sludge concentration in the first anaerobic ammonia oxidation reactor 4 is 16.0 g / L, and the NH4+ in the effluent... +-N, NO3 - -N and NO2 - -N concentrations were 115.9 mg / L, 180.9 mg / L, and 3.8 mg / L.

[0043] The effluent from the first anaerobic ammonia oxidation reactor 4, along with the carbon source (sodium acetate), is pumped into the short-cut denitrification-hydroxyapatite coupled reactor 6. The COD and NO3 in the short-cut denitrification-hydroxyapatite coupled reactor 6... - The NH4+-N mass concentration ratio is 2.4, the sludge concentration is 18.0 g / L, and the sludge retention time is 6 days. 25% of the sludge from the short-cut denitrification-hydroxyapatite coupled reactor is discharged into hydrocyclone 7. The sludge from the bottom of hydrocyclone 7 is pumped into short-cut denitrification reactor 2, and the sludge from the top is returned to short-cut denitrification-hydroxyapatite coupled reactor 6. The Ca / P mass concentration ratio in short-cut denitrification-hydroxyapatite coupled reactor 6 is approximately 3.0. The NH4+ in the effluent... + -N, NO3 - -N and NO2 - -N concentrations were 112.6 mg / L, 8.7 mg / L, and 157.1 mg / L.

[0044] The effluent from the short-cut denitrification-hydroxyapatite coupled reactor 6 is pumped into the second anaerobic ammonium oxidation reactor 9. The sludge concentration (MLSS) of the second anaerobic ammonium oxidation reactor 9 is controlled at 12.0 g / L during operation. The effluent NH4+... + -N and NO3 - The concentrations of -N were 2.1 mg / L and 4.2 mg / L, respectively.

[0045] Example 2 A system for treating fertilizer production wastewater and electroplating pickling wastewater under heavy metal stress, based on hydroxyapatite-enhanced PD / A process, is proposed. The fertilizer production wastewater contains NH4+. + -N: 492.1 mg / L, soluble phosphorus: 87.8 mg / L, pH approximately 7.0, COD: 172.3 mg / L. Electroplating pickling wastewater contains NH4+. + -N: 20.9 mg / L, NO3 - -N, 1345.8 mg / L, COD 230.9 mg / L, Cu 2+ : 12.4 mg / L, pH: 2.7.

[0046] Wastewater from fertilizer production and electroplating pickling was pumped into raw water tank 1 at a ratio of 2:1. The wastewater was then mixed, homogenized, and the pH was adjusted in raw water tank 1. NH4+ was added. + -N, NO3 - -N, soluble phosphorus, Cu 2+The concentrations of COD were 328.5 mg / L, 452.7 mg / L, 57.9 mg / L, 6.0 mg / L and 191.8 mg / L, respectively, and the pH was 7.3.

[0047] Mixed wastewater is pumped into short-cut denitrification reactor 2, where the sludge concentration is 13.0 g / L. 2.5 g / L of short-cut denitrification-hydroxyapatite coupled granular sludge is pumped into reactor 2 daily. Under operating conditions with a sludge retention time of 10 days, the NH4+ in the effluent... + -N, NO3 - -N and NO2 - -N concentrations were 323.7 mg / L, 408.5 mg / L, and 36.2 mg / L.

[0048] The effluent from the short-cut denitrification reactor 2 is pumped into the first anaerobic ammonia oxidation reactor 4. The sludge concentration in the first anaerobic ammonia oxidation reactor 4 is 14.0 g / L, and the NH4+ in the effluent... + -N, NO3 - -N and NO2 - -N concentrations were 299.9 mg / L, 411.3 mg / L, and 2.8 mg / L.

[0049] The effluent from the first anaerobic ammonia oxidation reactor 4, along with the carbon source (sodium acetate), is pumped into the short-cut denitrification-hydroxyapatite coupled reactor 6. The COD and NO3 in the short-cut denitrification-hydroxyapatite coupled reactor 6... - The -N mass concentration ratio is 2.3, the sludge concentration is 16.0 g / L, and the sludge retention time is 6 days. 20% of the sludge from the short-cut denitrification-hydroxyapatite coupled reactor is discharged into hydrocyclone 7. The sludge from the bottom of hydrocyclone 7 is pumped into short-cut denitrification reactor 2, and the sludge from the top is returned to short-cut denitrification-hydroxyapatite coupled reactor 6. The Ca / P mass concentration ratio in short-cut denitrification-hydroxyapatite coupled reactor 6 is approximately 3.0. The NH4+ in the effluent... + -N, NO3 - -N and NO2 - -N concentrations were 289.1 mg / L, 8.3 mg / L, and 358.8 mg / L.

[0050] The effluent from the short-cut denitrification-hydroxyapatite coupled reactor 6 is pumped into the second anaerobic ammonium oxidation reactor 9. The sludge concentration (MLSS) of the second anaerobic ammonium oxidation reactor 9 is controlled at 13.0 g / L during operation. The effluent NH4+... + -N and NO3 - The concentrations of -N were 2.8 mg / L and 3.9 mg / L, respectively.

[0051] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0052] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A process operation system for PD / A particles under HAP-enhanced heavy metal stress, characterized in that: The system includes a raw water tank (1), which is connected to a short-cut denitrification reactor (2). The short-cut denitrification reactor (2) is connected to a first intermediate water tank (3). The first intermediate water tank (3) is connected to a first anaerobic ammonia oxidation reactor (4). The first anaerobic ammonia oxidation reactor (4) is connected to a second intermediate water tank (5). The second intermediate water tank (5) is connected to a short-cut denitrification-hydroxyapatite coupled reactor (6). The short-cut denitrification-hydroxyapatite coupled reactor (6) is connected to a third intermediate water tank (8). The third intermediate water tank (8) is connected to a second anaerobic ammonia oxidation reactor (9). The short-cut denitrification reactor (2) and the short-cut denitrification-hydroxyapatite coupled reactor (6) are respectively connected to hydrocyclones (7).

2. The PD / A particle process operation system based on HAP-enhanced heavy metal stress according to claim 1, characterized in that: The short-cut denitrification reactor (2) includes a first stirrer (21) installed inside the short-cut denitrification reactor (2), the raw water tank (1) is connected to the first inlet (23) of the short-cut denitrification reactor (2) through a first inlet pump (22), and the first outlet (24) of the short-cut denitrification reactor (2) is connected to the first intermediate water tank (3).

3. The PD / A particle process operation system based on HAP-enhanced heavy metal stress according to claim 1, characterized in that: The bottom of the short-range denitrification reactor (2) is provided with a first sludge inlet (26), which is connected to the hydrocyclone (7) through a first sludge pump (25).

4. The HAP-enhanced PD / A particle process operation system under heavy metal stress according to claim 1, characterized in that: The bottom of the first anaerobic ammonia oxidation reactor (4) is provided with a second water inlet (42), which is connected to a second water inlet pump (41) and a first reflux pump (44). The second water inlet pump (41) is connected to the first intermediate water tank (3), and the first reflux pump (44) is connected to a first reflux port (43). The first reflux port (43) is connected to the top of the first anaerobic ammonia oxidation reactor (4). The top of the first anaerobic ammonia oxidation reactor (4) is also provided with a second drain outlet (45), which is connected to the second intermediate water tank (5). The second drain outlet (45) is located above the first reflux port (43).

5. The PD / A particle process operation system based on HAP-enhanced heavy metal stress according to claim 1, characterized in that: The short-cut denitrification-hydroxyapatite coupled reactor (6) is equipped with a second stirrer (61). The top of the short-cut denitrification-hydroxyapatite coupled reactor (6) is connected to a carbon source storage tank (64) and a calcium source storage tank (67). The short-cut denitrification-hydroxyapatite coupled reactor (6) is provided with a third inlet (63) on the side near the second intermediate water tank (5). The third inlet (63) is connected to the second intermediate water tank (5) through a third inlet pump (62). The side of the short-cut denitrification-hydroxyapatite coupled reactor (6) away from the second intermediate water tank (5) is connected to the third intermediate water tank (8) through a third outlet (610). The short-cut denitrification-hydroxyapatite coupled reactor (6) is connected to the hydrocyclone (7) through a first sludge discharge port (611) and a second sludge inlet (615).

6. The HAP-enhanced PD / A particle process operation system under heavy metal stress according to claim 5, characterized in that: The short-range denitrification-hydroxyapatite coupled reactor (6) is connected to the carbon source storage tank (64) through the fourth inlet (66) and the fourth inlet pump (65), and the short-range denitrification-hydroxyapatite coupled reactor (6) is connected to the calcium source storage tank (67) through the fifth inlet pump (68) and the fifth inlet (69).

7. The HAP-enhanced PD / A particle process operation system under heavy metal stress according to claim 5, characterized in that: A first sludge discharge pump (612) is connected between the first sludge discharge port (611) and the hydrocyclone (7), and a second sludge inlet pump (614) is connected between the second sludge inlet (615) and the hydrocyclone (7).

8. The PD / A particle process operation system based on HAP-enhanced heavy metal stress according to claim 1, characterized in that: The bottom of the second anaerobic ammonia oxidation reactor (9) is provided with a sixth inlet (92), which is connected to the third intermediate water tank (8) through a sixth inlet pump (91). The sixth inlet (92) is connected to a second reflux port (93) through a second reflux pump (94). The second reflux port (93) is located at the top of the second anaerobic ammonia oxidation reactor (9). A fourth drain port (95) is provided above the second reflux port (93), which is connected to an outlet tank.

9. The HAP-enhanced PD / A particle process operation system under heavy metal stress according to claim 1, characterized in that: The raw water tank (1) contains heavy metals and NO3. - -N industrial wastewater and NH4-containing + -N industrial wastewater.

10. An operation method for a PD / A particle process operating system under HAP-enhanced heavy metal stress, based on the PD / A particle process operating system under HAP-enhanced heavy metal stress as described in any one of claims 1-9, characterized in that, Includes the following steps: S1, containing heavy metals and NO3 - -N industrial wastewater and NH4-containing + -N industrial wastewater is pumped into raw water tank (1) to adjust the pH of the wastewater in raw water tank (1) to 6.5-8.0, and NO3- - -N / NH4 + The -N mass concentration ratio is 1.0-2.0, and the COD and NO3 concentrations are... - The ratio of -N mass concentration is less than 3.0, and the ratio of total nitrogen to dissolved phosphorus mass concentration is less than 20.0; S2. Pump the mixed wastewater from the raw water tank (1) into the short-cut denitrification reactor (2), with a sludge concentration of 10.0-16.0 g / L and a sludge retention time of 8-15 days; S3. Pump the effluent from the short-cut denitrification reactor (2) into the first anaerobic ammonia oxidation reactor (4), and control the sludge concentration of the first anaerobic ammonia oxidation reactor (4) to be 5.0-20.0 g / L during operation. The effluent NO2 - -N concentration less than 5.0 mg / L; S4. The effluent from the first anaerobic ammonia oxidation reactor (4) and the carbon source are pumped together into the short-cut denitrification-hydroxyapatite coupled reactor (6) to control the COD and NO3 levels in the short-cut denitrification-hydroxyapatite coupled reactor (6). - The NO3-N mass concentration ratio is 2.0-4.

0. Calcium chloride and calcium hydroxide are used to adjust the Ca / P mass concentration ratio of the short-cut denitrification-hydroxyapatite coupled reactor (6) to 2.0-5.

0. The sludge concentration of the short-cut denitrification-hydroxyapatite coupled reactor (6) is controlled at 15.0-25.0 g / L, and the sludge retention time is 5-10 days. The effluent NO3- - -N concentration less than 10.0 mg / L; S5. Pump the effluent from the short-cut denitrification-hydroxyapatite coupled reactor (6) into the second anaerobic ammonium oxidation reactor (9). Control the sludge concentration (MLSS) of the second anaerobic ammonium oxidation reactor (9) to be 10.0-20.0 g / L during operation. The effluent NH4 + -N concentration less than 3.0 mg / L, NO3 - -N concentration less than 5.0 mg / L; In step S2, 1.5-4.0 g / L of short-cut denitrification-hydroxyapatite coupled granular sludge is pumped into the short-cut denitrification reactor (2) every day; In step S3, NO2 in the effluent - When the NO2 concentration is greater than 5.0 mg / L, the sludge retention time in the first anaerobic ammonia oxidation reactor (4) is extended until the effluent NO2 - -N concentration less than 5.0 mg / L; In step S4, NO3 in the effluent - When the -N concentration is greater than 10.0 mg / L, it increases COD and NO3. - -N mass concentration ratio until NO3 in the effluent - -N concentration less than 10.0 mg / L; In step S4, 15-40% of the sludge is discharged into the hydrocyclone (7), the sludge at the bottom of the hydrocyclone (7) is pumped into the short-cut denitrification reactor (2), and the sludge at the top is returned to the short-cut denitrification-hydroxyapatite coupled reactor (6). In step S5, NH4 + When the NO3- concentration is greater than 3.0 mg / L, the NO3- concentration in the mixed influent of the short-cut denitrification reactor (2) is increased. - -N and NH4 + -N mass concentration ratio until the NH4 in the effluent of the second anaerobic ammonia oxidation reactor (9) + -N concentration less than 3.0 mg / L; NO3 - When the NO3- concentration is greater than 5.0 mg / L, extend the hydraulic retention time of the second anaerobic ammonia oxidation reactor (9) until the effluent NO3- - -N concentration less than 5.0 mg / L; NH4 + -N concentration greater than 3.0 mg / L and NO3 - When the -N concentration is greater than 5.0 mg / L, the COD and NO3 of the short-path denitrification-hydroxyapatite coupled reactor (6) are increased. - -N mass concentration ratio until NH4 in the effluent + -N concentration less than 3.0 mg / L and NO3 - -N concentration less than 5.0 mg / L.

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