Column type short-cut nitrification-anaerobic ammonia oxidation reactor and sewage treatment process

Abstract

The invention relates to the technical field of water treatment, in particular to a column type shortcut nitrification-anaerobic ammonia oxidation reactor and a sewage treatment process. Comprising a column type container; a shortcut nitrification zone, an anaerobic ammonia oxidation zone, a buffer zone, a sludge storage zone and on-line monitoring equipment are arranged in the column type container; the short-cut nitrification area is used for receiving the sewage subjected to organic matter removal, carbon removal and phosphorus removal, and carrying out ammoxidation treatment on the sewage; the anaerobic ammonia oxidation zone is used for carrying out anaerobic ammonia oxidation treatment on ammonia nitrogen and nitrite in the sewage subjected to ammonia oxidation treatment; the buffer area is used for receiving returned sludge in the anaerobic ammonia oxidation area, treating the received sludge and conveying the treated sludge into the short-cut nitrification area; the sludge storage area is used for receiving sludge; the online monitoring equipment is used for detecting DO, pH, T, ORP and temperature of sewage in real time. According to the method, the defects of large occupied area and high capital construction and operation cost of traditional sewage treatment are overcome, and meanwhile, the two-section type sludge backflow energy consumption is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of water treatment, and in particular to a column-type short-range nitrification-anaerobic ammonium oxidation reactor and a sewage treatment process. Background Art

[0002] With the increasingly stringent requirements for sewage treatment, traditional heterotrophic denitrification technology faces many limitations, which has prompted the development of autotrophic denitrification technology. Traditional heterotrophic denitrification relies on organic carbon sources, but many sewages lack carbon sources and require additional additions, which is costly and increases the complexity of treatment. At the same time, excessive organic carbon sources can easily cause microbial proliferation, resulting in a sharp increase in sludge production and difficulties in subsequent treatment and disposal. In addition, during heterotrophic denitrification, competition for organic carbon sources by microorganisms may affect the efficiency and stability of denitrification. Autotrophic denitrification technology uses inorganic compounds as electron donors and does not require additional carbon sources. It can effectively solve the problem of insufficient carbon sources, reduce sludge production, improve the economy and stability of the denitrification process, and adapt to a wider range of sewage treatment scenarios. It is of key significance in the process of water resource protection and sustainable development.

[0003] However, the two-stage and integrated PN / A processes have their own shortcomings. The two-stage process occupies a large area, has high infrastructure and operating costs, and the sludge return system increases system complexity and energy consumption; the integrated process has the disadvantages of complex and time-consuming reactor startup, high control difficulty, and weak impact resistance. Therefore, it is urgent to solve the problem.

[0004] The above contents are only used to assist in understanding the technical solution of the present invention, and do not constitute an admission that the above contents are the closest prior art. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a columnar short-range nitrification-anaerobic ammonium oxidation reactor and a sewage treatment process, which solves the defects of traditional sewage treatment, such as large footprint, high infrastructure and operation costs, and reduces the energy consumption of two-stage sludge return.

[0006] To achieve the above object, the technical solution of the present invention is implemented as follows: a columnar short-range nitrification-anaerobic ammonium oxidation reactor and a sewage treatment process, comprising a columnar container; the columnar container is provided with a short-range nitrification zone, an anaerobic ammonium oxidation zone, a buffer zone, a mud storage zone and an online monitoring device; the short-range nitrification zone is connected to the sewage pretreatment zone, and is used to receive sewage after organic matter is removed, carbon is removed, and phosphorus is removed, and the sewage is subjected to ammonia oxidation treatment;

[0007] The anaerobic ammonium oxidation zone is connected to the short-range nitrification zone, and is used to perform anaerobic ammonium oxidation treatment on ammonia nitrogen and nitrite in the sewage after the ammonia oxidation treatment;

[0008] The buffer zone is connected to both the short-cut nitrification zone and the anaerobic ammonium oxidation zone, and is used to receive the return sludge in the anaerobic ammonium oxidation zone, and transport the received sludge to the short-cut nitrification zone after treatment;

[0009] The sludge storage area is connected to the anaerobic ammonium oxidation area and is used to receive sludge;

[0010] The online monitoring equipment is used to perform real-time detection of DO, pH, T, ORP and temperature of sewage in the short-range nitrification zone and the anaerobic ammonium oxidation zone.

[0011] Preferably, the short-range nitrification zone, the anaerobic ammonium oxidation zone and the buffer zone are located at the same layer of the column container; and the sludge storage zone is located at the bottom of the short-range nitrification zone, the anaerobic ammonium oxidation zone and the buffer zone.

[0012] Preferably, the water flow through the short-range nitrification zone and the anaerobic ammonium oxidation zone is carried out by using an inverted U-shaped tube.

[0013] Preferably, the hydraulic retention time HRT of the short-range nitrification zone is 1 to 3 days, the sludge retention time SRT is 10 to 20 days, the dissolved oxygen DO is 0.5 to 1.0 mg / L, the pH is 7.5 to 8.5, and the redox potential ORP is +100 to +200 mV; the anaerobic ammonia oxidation zone: HRT is 0.5 to 2 days, SRT is 30 to 50 days, DO < 0.2 mg / L, pH is 6.7 to 8.3, and ORP is -100 to -300 mV.

[0014] Preferably, the short-range nitrification zone is provided with a microporous aeration disk; the microporous aeration disk is used to provide dissolved oxygen for the ammonia oxidizing bacteria AOB in the sewage in the short-range nitrification zone to oxidize ammonia nitrogen into nitrite nitrogen.

[0015] Preferably, the sludge return in the buffer zone is carried out by means of a through-wall pump and a matching gate, and the sludge return is completed in the form of diversion, with intermittent operation.

[0016] Preferably, the anaerobic ammonium oxidation zone is provided with a hyperbolic three-dimensional fan-shaped agitator; the three-dimensional fan-shaped agitator is used to stir the ammonia nitrogen and nitrite in the anaerobic ammonium oxidation zone.

[0017] Preferably, the buffer zones are each provided with a hyperbolic three-dimensional fan-shaped agitator and a microporous aeration disk.

[0018] Preferably, it also includes a solar heat transfer plate; the solar heat transfer plate is arranged between the inner shell and the outer shell of the column container, and the solar heat transfer plate adopts a solar hot water circulation mode to control the reaction temperature of the anaerobic ammonia oxidation zone to 30°C-40°C, and the reaction temperature of the short-range nitrification zone to 25°C-35°C.

[0019] Preferably, the sewage treatment process comprises:

[0020] S1. The sewage first enters the sewage pretreatment process section outside the column container to remove organic matter. After carbon removal and phosphorus removal, the sewage enters the short-range denitrification zone of the column container. In the short-range denitrification zone, the sewage completes the ammonia oxidation process, and under the action of AOB, the ammonia nitrogen in the sewage is converted into nitrite.

[0021] S2. The sewage enters the anaerobic ammonium oxidation zone through an inverted U-shaped pipe, and the pH, DO and temperature and other operating parameters in the anaerobic ammonium oxidation zone are controlled to achieve rapid anaerobic ammonium oxidation of ammonia nitrogen and nitrite, which are removed into nitrogen and discharged into the air;

[0022] S3. When it is detected that the short-range nitrification zone needs to be supplemented with sludge, the gate and the through-wall pump on the partition wall between the anaerobic ammonium oxidation zone and the buffer zone are opened, and the sludge in the anaerobic ammonium oxidation zone is discharged into the buffer zone, and then the gate of the partition wall is closed; stirring and micro-aeration are turned on, and after homogenization treatment after 0.5-1.0h, the water and sludge in the buffer zone are combined at the same time, and the gate and the through-wall pump on the partition wall between the buffer zone and the short-range denitrification zone are opened to return the mixed liquid in the buffer zone to the short-range denitrification zone to complete the sludge return;

[0023] S4. When the remaining sludge in the anaerobic ammonium oxidation zone needs to be discharged, open the external sludge discharge valve outside the column container, and the sludge is discharged into the lower sludge storage area through the semi-conical sludge hoppers in the anaerobic ammonium oxidation zone and the sludge storage area.

[0024] The beneficial effects of the present invention are embodied in:

[0025] (1) The column-type container provided by the present invention effectively cuts two adjacent large sections of the biochemical treatment environment through an inverted U-shaped tube, thereby reducing operating energy consumption; a sludge return system is added in the form of a through-wall pump, thereby improving the system's ability to withstand shock loads in a low-carbon manner.

[0026] (2) The buffer zone system provided by the present invention ensures that the return sludge does not affect the short-range denitrification environment by mixing with the influent and pre-aerating.

[0027] (3) The solar heat transfer plate provided by the present invention not only effectively guarantees the optimal temperature required for short-range nitrification and anaerobic ammonium oxidation reactions, but also is more energy-efficient and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is the sewage treatment flow chart of the present invention;

[0029] Figure 2 It is a schematic diagram of the arrangement of the inverted U-shaped tube of the present invention;

[0030] Figure 3 Schematic diagram of the spatial layout of the columnar container of the present invention. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0032] Example 1

[0033] like Figure 1-3 As shown, a column-type short-cut nitrification-anaerobic ammonium oxidation reactor and a sewage treatment process;

[0034] It includes: a column container; a short-range nitrification zone, an anaerobic ammonium oxidation zone, a buffer zone, a sludge storage zone and an online monitoring device are arranged in the column container. The short-range nitrification zone, the anaerobic ammonium oxidation zone and the buffer zone are located on the same layer of the column container; the sludge storage zone is located at the bottom of the short-range nitrification zone, the anaerobic ammonium oxidation zone and the buffer zone.

[0035] The short-range nitrification zone is connected to the sewage pretreatment zone, and is used to receive sewage after the removal of organic matter, carbon removal, and phosphorus removal, and to perform ammonia oxidation treatment on the sewage.

[0036] The anaerobic ammonium oxidation zone is connected to the short-range nitrification zone and is used to perform anaerobic ammonium oxidation treatment on ammonia nitrogen and nitrite in the sewage after the ammonia oxidation treatment.

[0037] The buffer zone is connected to both the short-range nitrification zone and the anaerobic ammonium oxidation zone, and is used to receive the return sludge in the anaerobic ammonium oxidation zone, and transport the received sludge to the short-range nitrification zone after treatment.

[0038] The sludge storage area is connected to the anaerobic ammonium oxidation area for receiving sludge.

[0039] Online monitoring equipment is used to conduct real-time detection of DO, pH, T, ORP and temperature of sewage in the short-range nitrification zone and anaerobic ammonium oxidation zone. Online monitoring equipment is generally an instrument facility that can detect DO, pH, T, ORP, etc. online, including: pH / oxidation-reduction potential (ORP) online analyzer (including temperature digital display), dissolved oxygen (DO) online detector.

[0040] In the short-range nitrification area, microporous aeration plates are set up to provide sufficient dissolved oxygen for the ammonia oxidizing bacteria AOB to oxidize ammonia nitrogen into nitrite nitrogen, and an online dissolved oxygen meter is set up to monitor the DO, T, pH and ORP in the area to ensure the short-range nitrification environment and the accumulation of nitrite.

[0041] During specific operation, the hydraulic retention time HRT of the short-range nitrification zone is 1 to 3 days, the sludge retention time SRT is 10 to 20 days, the dissolved oxygen DO is 0.5 to 1.0 mg / L, the pH is 7.5 to 8.5, and the redox potential ORP is +100 to +200 mV; anaerobic ammonia oxidation zone: HRT is 0.5 to 2 days, SRT is 30 to 50 days, DO <0.2 mg / L, pH is 6.7 to 8.3, and ORP is -100 to -300 mV.

[0042] like Figure 2 As shown: The water flow method for the short-range nitrification zone and the anaerobic ammonium oxidation zone adopts an inverted U-shaped tube to prevent backflow and reduce the mutual influence of water flows in two different environmental areas.

[0043] In the anaerobic ammonium oxidation zone, the ammonia nitrogen and nitrite in the zone are stirred and fully mixed by a hyperbolic three-dimensional fan-shaped agitator to achieve the anaerobic ammonium oxidation reaction of ammonia nitrogen and nitrite, remove nitrogen, and simultaneously set up an online dissolved oxygen meter to monitor the DO, T, pH and ORP of the area, so as to timely regulate and ensure the environment of the anaerobic ammonium oxidation biochemical reaction.

[0044] In addition, in the anaerobic ammonium oxidation zone, less residual sludge is discharged into the lower sludge storage area through a semi-conical connecting pipe. It can be opened and closed by the valve outside the column reactor after stopping stirring and standing for a period of time, and the amount of sludge discharged is calculated by the liquid level. Gravity flow reduces operating energy consumption.

[0045] By setting up a buffer area, when ammonia oxidation sludge needs to be supplemented in the short-term nitrification zone, the return sludge first enters the buffer zone from the anaerobic ammonia oxidation zone. After being fully mixed with the influent through the stirring device, the water quality and environmental conditions gradually transition before entering the short-term nitrification zone to avoid ammonia oxidizing bacteria being suddenly exposed to different environments. The buffer zone residence time can be set to 0.5 to 1.0 h.

[0046] The sludge return in the buffer area is achieved by a through-the-wall pump and a matching gate. The through-the-wall pump has lower power than traditional sewage pumps, completes the sludge return in the form of diversion, operates intermittently, has low energy consumption, and meets low-carbon requirements.

[0047] Hyperbolic solid fan-shaped agitators are installed in both the anaerobic ammonium oxidation zone and the buffer zone, and a small number of microporous aeration disks are arranged in the buffer zone. In order to ensure sufficient contact between microorganisms and sewage in the anaerobic ammonium oxidation zone, a double-layer agitator is used to form an upward flow to reduce dead corners in the reaction zone. The agitator arranged in the buffer zone is mainly used to homogenize the return sludge and part of the incoming water, and then return to the short-range nitrification zone after forming a transition environment. At the same time, a small amount of aeration is also carried out to create an environment similar to the short-range nitrification zone.

[0048] It also includes a solar heat transfer plate; the solar heat transfer plate is arranged between the inner shell and the outer shell of the column container, and the solar heat transfer plate adopts a solar hot water circulation mode to control the reaction temperature of the anaerobic ammonia oxidation zone to 30°C to 40°C, and controls the reaction temperature of the short-range nitrification zone to 25°C to 35°C.

[0049] Example 2

[0050] Wastewater treatment processes include:

[0051] S1. Sewage first enters the pretreatment process section to remove organic matter. After carbon and phosphorus removal, the sewage enters the short-range denitrification area of ​​the column device. In this area, the sewage completes the ammonia oxidation process. Under the action of AOB, the ammonia nitrogen in the sewage is converted into nitrite and accumulates to a certain concentration. The microenvironment in the area is controlled by pH adjustment, aeration control of DO, heat transfer plate regulation of T, etc.

[0052] During the specific operation, industrial hydrochloric acid is accurately added to the short-range denitrification zone to ensure that the pH of the reaction is around pH = 7.5;

[0053] The aeration volume is then regulated by controlling the frequency of the blower's variable frequency motor and the valve opening to ensure that the DO concentration is maintained at around 0.8 mg / L.

[0054] Finally, the temperature of the circulating hot water is set at around 30°C through the solar photovoltaic panels and the control system.

[0055] S2. Sewage enters the anaerobic ammonium oxidation zone through an inverted U-shaped pipe, but due to the long pipe between the short-range denitrification zone and the anaerobic ammonium oxidation zone, the back-mixing phenomenon caused by sewage mixing is avoided. Control the operating parameters such as pH, DO and temperature in the anaerobic ammonium oxidation zone.

[0056] In specific operation, industrial hydrochloric acid is accurately added into the anaerobic ammonium oxidation zone to ensure that the pH value of the reaction is around pH=8.0.

[0057] The DO concentration in the anaerobic ammonium oxidation zone is fine-tuned by controlling the frequency of the variable frequency motor of the agitator to maintain it at around 0.1 mg / L.

[0058] The temperature of circulating hot water is set at about 35°C through solar photovoltaic panels and control systems. Ammonia nitrogen and nitrite are quickly anaerobicly oxidized to nitrogen and discharged into the air.

[0059] S3. When it is detected that sludge needs to be supplemented in the short-range nitrification zone, the gate and the through-wall pump on the partition wall between the anaerobic ammonium oxidation zone and the buffer zone are opened, and the sludge in the anaerobic ammonium oxidation zone is discharged into the buffer zone, and then the gate of the partition wall is closed; stirring and micro-aeration are turned on, and after 0.5-1.0h of homogenization treatment, the water and sludge in the buffer zone are combined at the same time, and the gate and the through-wall pump on the partition wall between the buffer zone and the short-range denitrification zone are opened to return the mixed liquid in the buffer zone to the short-range denitrification zone to complete the sludge return.

[0060] S4. When the remaining sludge in the anaerobic ammonium oxidation zone needs to be discharged, open the external sludge discharge valve outside the column container, and the sludge is discharged into the lower sludge storage area through the semi-conical sludge hoppers in the anaerobic ammonium oxidation zone and the sludge storage area. The sludge in the sludge storage area enters the next treatment and disposal process.

[0061] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A column-type short-cut nitrification-anaerobic ammonium oxidation reactor, characterized in that: It comprises a column container; the column container is provided with a short-range nitrification zone, an anaerobic ammonia oxidation zone, a buffer zone, a sludge storage zone and an online monitoring device; the short-range nitrification zone is connected with the sewage pretreatment zone, and is used to receive sewage after organic matter is removed, carbon is removed, and phosphorus is removed, and the sewage is subjected to ammonia oxidation treatment; The anaerobic ammonium oxidation zone is connected to the short-range nitrification zone, and is used to perform anaerobic ammonium oxidation treatment on ammonia nitrogen and nitrite in the sewage after the ammonia oxidation treatment; The buffer zone is connected to both the short-cut nitrification zone and the anaerobic ammonium oxidation zone, and is used to receive the return sludge in the anaerobic ammonium oxidation zone, and transport the received sludge to the short-cut nitrification zone after treatment; The sludge storage area is connected to the anaerobic ammonium oxidation area and is used to receive sludge; The online monitoring equipment is used to perform real-time detection of DO, pH, T, ORP and temperature of sewage in the short-range nitrification zone and the anaerobic ammonium oxidation zone.

2. A column-type short-cut nitrification-anaerobic ammonium oxidation reactor according to claim 1, characterized in that: The short-range nitrification zone, the anaerobic ammonium oxidation zone and the buffer zone are located at the same layer of the column container; the sludge storage zone is located at the bottom of the short-range nitrification zone, the anaerobic ammonium oxidation zone and the buffer zone.

3. A column-type short-cut nitrification-anaerobic ammonium oxidation reactor according to claim 1 or 2, characterized in that: The water flow through the short-range nitrification zone and the anaerobic ammonia oxidation zone is carried out by using an inverted U-shaped tube.

4. A column-type short-cut nitrification-anaerobic ammonium oxidation reactor according to claim 3, characterized in that: The hydraulic retention time HRT of the short-range nitrification zone is 1 to 3 days, the sludge retention time SRT is 10 to 20 days, the dissolved oxygen DO is 0.5 to 1.0 mg / L, the pH is 7.5 to 8.5, and the redox potential ORP is +100 to +200 mV; the anaerobic ammonia oxidation zone: HRT is 0.5 to 2 days, SRT is 30 to 50 days, DO is less than 0.2 mg / L, pH is 6.7 to 8.3, and ORP is -100 to -300 mV.

5. A column-type short-cut nitrification-anaerobic ammonium oxidation reactor according to claim 4, characterized in that: The short-range nitrification zone is provided with a microporous aeration disk; the microporous aeration disk is used to provide dissolved oxygen for the ammonia oxidizing bacteria AOB in the sewage in the short-range nitrification zone to oxidize ammonia nitrogen into nitrite nitrogen.

6. A column-type short-cut nitrification-anaerobic ammonium oxidation reactor according to claim 5, characterized in that: The buffer zone sludge return is achieved by the combination of a through-wall pump and a matching gate, and the sludge return is completed in the form of diversion, with intermittent operation.

7. A column-type short-cut nitrification-anaerobic ammonium oxidation reactor according to claim 5, characterized in that: The anaerobic ammonium oxidation zone is provided with a hyperbolic three-dimensional fan-shaped agitator; the three-dimensional fan-shaped agitator is used to stir the ammonia nitrogen and nitrite in the anaerobic ammonium oxidation zone.

8. A column-type short-cut nitrification-anaerobic ammonium oxidation reactor according to claim 7, characterized in that: The buffer zones are all provided with hyperbolic three-dimensional fan-shaped stirrers and microporous aeration disks.

9. A column-type short-cut nitrification-anaerobic ammonium oxidation reactor according to claim 5, characterized in that: It also includes a solar heat transfer plate; the solar heat transfer plate is arranged between the inner shell and the outer shell of the column container, and the solar heat transfer plate adopts a solar hot water circulation mode to control the reaction temperature of the anaerobic ammonia oxidation zone to 30°C to 40°C, and the reaction temperature of the short-range nitrification zone to 25°C to 35°C.

10. A sewage treatment process using a column-type short-cut nitrification-anaerobic ammonium oxidation reactor according to any one of claims 1 to 9, characterized in that: The sewage treatment process comprises: S1. The sewage first enters the sewage pretreatment process section outside the column container to remove organic matter. After carbon removal and phosphorus removal, the sewage enters the short-range denitrification zone of the column container. In the short-range denitrification zone, the sewage completes the ammonia oxidation process, and under the action of AOB, the ammonia nitrogen in the sewage is converted into nitrite. S2. The sewage enters the anaerobic ammonium oxidation zone through an inverted U-shaped pipe, and the pH, DO and temperature and other operating parameters in the anaerobic ammonium oxidation zone are controlled to achieve rapid anaerobic ammonium oxidation of ammonia nitrogen and nitrite, which are removed into nitrogen and discharged into the air; S3. When it is detected that the short-range nitrification zone needs to be supplemented with sludge, the gate and the through-wall pump on the partition wall between the anaerobic ammonium oxidation zone and the buffer zone are opened, and the sludge in the anaerobic ammonium oxidation zone is discharged into the buffer zone, and then the gate of the partition wall is closed; stirring and micro-aeration are turned on, and after homogenization treatment after 0.5-1.0h, the water and sludge in the buffer zone are combined at the same time, and the gate and the through-wall pump on the partition wall between the buffer zone and the short-range denitrification zone are opened to return the mixed liquid in the buffer zone to the short-range denitrification zone to complete the sludge return; S4. When the remaining sludge in the anaerobic ammonium oxidation zone needs to be discharged, open the external sludge discharge valve outside the column container, and the sludge is discharged into the lower sludge storage area through the semi-conical sludge hoppers in the anaerobic ammonium oxidation zone and the sludge storage area.

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