Pilot plant for sulfur autotrophic denitrification filter

Abstract

The utility model discloses a pilot plant for a sulfur autotrophic denitrification filter tank, which comprises a dosing and water distribution system for changing the concentration of nitrate in inlet water; the input end of the reactor system is connected with the dosing water distribution system, and the reactor system comprises a gravity flow reactor and an upward flow reactor; wherein the gravity flow reactor and the upward flow reactor are internally provided with filter material layers, and the filter material layers are sulfur autotrophic denitrification filler; the clear water tank is communicated with the output end of the reactor system; the monitoring system is used for monitoring parameter changes after the water flow passes through the gravity flow reactor and the upward flow reactor; and the backwashing system is arranged between the clear water tank and the reactor system. The utility model relates to the technical field of biological sewage treatment, and by virtue of the arrangement, the denitrification effect of a reactor system can be simulated when the reactor system deals with various types of sewage under different water qualities and working conditions, so that an operator can conveniently carry out optimization design on the reactor system according to the denitrification effect, and accurate reference is provided for subsequent engineering application.

Description

Technical Field

[0001] The utility model belongs to the field of environmental protection, relates to sewage biological treatment technology, and specifically is a pilot-scale device for sulfur autotrophic denitrification filter. Background Technique

[0002] The nitrogen content is one of the important indicators for evaluating water quality. The traditional heterotrophic denitrification process is currently the mainstream biological nitrogen removal technology, and its high efficiency and wide applicability are widely recognized. However, this process is significantly limited by the carbon source supply. Most municipal sewage has the characteristics of a low carbon-nitrogen ratio and requires additional organic carbon sources to maintain the high efficiency of heterotrophic denitrification, which not only increases the operating cost but also leads to more carbon emissions.

[0003] In recent years, autotrophic biological nitrogen removal processes have been widely promoted due to their advantages such as no need for external organic carbon sources, low cost, and low sludge production. As an important representative of autotrophic denitrification processes, sulfur autotrophic denitrification uses sulfur autotrophic bacteria under anoxic or anaerobic conditions, with reduced sulfur (S 2- 、S 0 、S2O3 2- etc.) as the electron donor to reduce nitrate to nitrogen gas, thereby realizing the denitrification and nitrogen removal process. Due to the characteristic of no need for external carbon sources, sulfur autotrophic denitrification overcomes the limitations of the heterotrophic denitrification process to a certain extent, significantly reduces carbon emissions, and has obvious carbon reduction benefits.

[0004] Although sulfur autotrophic denitrification technology shows potential in theoretical and laboratory research, the current application of this technology in engineering practice still faces many challenges and limitations. For example, most existing research is limited to experiments under simulated sewage conditions, and there are significant differences compared with the complexity and diversity of real municipal sewage. The treatment scale in the laboratory is usually small, and the filler materials, process parameters, etc. used are different, which makes it impossible to fully verify the consistency and stability of the technology and is difficult to directly apply it in engineering.

[0005] Therefore, a pilot-scale device for sulfur autotrophic denitrification filter is needed to achieve efficient nitrogen removal of various sewage under different water qualities and working conditions, and provide accurate reference for subsequent engineering applications. Content of the Utility Model

[0006] The present utility model aims to solve at least one of the technical problems existing in the prior art; for this purpose, the present utility model provides a pilot-scale device for sulfur autotrophic denitrification filter, which can simulate the denitrification effect of the reactor system when dealing with various sewage under different water qualities and working conditions, facilitating the operator to optimize the design of the reactor system according to the denitrification effect, enabling efficient denitrification of various sewage under different water qualities and working conditions, and thus providing accurate reference for subsequent engineering applications. The present utility model combines the sulfur autotrophic denitrification technology with the existing denitrification deep bed filter technology by setting a chemical dosing and water distribution system, a reactor system with a filter layer formed by sulfur autotrophic denitrification fillers, a backwashing system and a monitoring system, and regulates the nitrate concentration in the influent through the chemical dosing and water distribution system to simulate the operation under different water qualities and working conditions, so as to obtain the denitrification effects of the gravity flow reactor and the upflow reactor under different water qualities and working conditions, and optimize the design of the reactor system according to the denitrification effect, and further provide accurate reference for subsequent engineering applications.

[0007] To achieve the above object, a first aspect of the present utility model provides a pilot-scale device for sulfur autotrophic denitrification filter, comprising:

[0008] A chemical dosing and water distribution system for changing the nitrate concentration in the influent to conduct nitrate concentration gradient tests;

[0009] A reactor system, the input end of which is connected to the chemical dosing and water distribution system, and includes a gravity flow reactor and an upflow reactor arranged in parallel;

[0010] Wherein, a filter layer is provided inside both the gravity flow reactor and the upflow reactor, and the filter layer is sulfur autotrophic denitrification filler;

[0011] A clear water tank, which is communicated with the output end of the reactor system;

[0012] A monitoring system for monitoring the parameter changes of the water flow after passing through the gravity flow reactor and the upflow reactor;

[0013] A backwashing system, which is arranged between the clear water tank and the reactor system, and is used for regularly washing the gravity flow reactor and the upflow reactor with water, washing with gas or combined water and gas washing.

[0014] Further, a first backwashing pipeline and a second backwashing pipeline are respectively communicated between the clear water tank and the gravity flow reactor and the upflow reactor;

[0015] The backwashing system is arranged on the first backwashing pipeline and the second backwashing pipeline, and includes two backwashing water pumps and a backwashing blower for washing the gravity flow reactor and the upflow reactor with water, washing with gas or combined water and gas washing.

[0016] Further, the two backwashing water pumps are respectively arranged on the first backwashing pipeline and the second backwashing pipeline;

[0017] The backwashing blower is communicated with the first backwashing pipeline and the second backwashing pipeline respectively through pipelines.

[0018] Further, first flow meters are arranged on both the first backwashing pipeline and the second backwashing pipeline for detecting the backwashing water volume.

[0019] Further, a second flow meter is arranged between the chemical dosing and water distribution system and the reactor system for detecting the water inflow of the gravity flow reactor and the upflow reactor.

[0020] Further, triangular weir plates and support layers are also respectively arranged inside the gravity flow reactor and the upflow reactor;

[0021] The triangular weir plates, the filter media layer and the support layer are arranged from top to bottom.

[0022] Further, the thickness of the filter media layer is one-third to one-half of the height of the gravity flow reactor or the upflow reactor.

[0023] Further, the monitoring system includes on-line monitoring instruments.

[0024] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0025] By arranging a chemical dosing and water distribution system, a reactor system with a filter media layer formed by sulfur autotrophic denitrification fillers, a clean water tank, a monitoring system and a backwashing system, the sulfur autotrophic denitrification technology is combined with the existing denitrification deep bed filter technology, and the nitrate concentration in the influent water is regulated by means of the chemical dosing and water distribution system to simulate the operation under different water qualities and working conditions, so as to obtain the denitrification effects of the gravity flow reactor and the upflow reactor under different water qualities and working conditions, and optimize the design of the reactor system according to the denitrification effects, and further can provide accurate reference for subsequent engineering applications.

[0026] Moreover, the filter media layer can be backwashed in time by means of the backwashing system to remove the intercepted suspended substances and the proliferated microorganisms, thereby reducing the head loss.

[0027] Among them, the filter media layer uses sulfur autotrophic denitrification fillers. Since sulfur autotrophic denitrification fillers do not require additional organic carbon sources during application and have a lower backwashing frequency compared to traditional filter media, the purpose of reducing sludge production rate and operating cost is achieved, and the denitrification effect can also be effectively improved. In addition, due to the characteristics of short residence time and high denitrification load of the sulfur autotrophic denitrification filter, the floor area required for this device can be effectively saved and the space utilization rate can be improved. Brief Description of the Drawings

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0029] Figure 1 It is a schematic structural diagram of the pilot-scale device of sulfur autotrophic denitrification filter of the present invention.

[0030] Reference Numerals in the Drawings:

[0031] 1. Chemical dosing and water distribution system; 2. Gravity flow reactor; 3. Upflow reactor; 4. Clear water tank; 5. Monitoring system; 6. Backwashing system; 61. Backwashing water pump; 62. Backwashing air blower; 7. First flowmeter; 8. Second flowmeter; 9. V-notch weir plate; 10. Filter media layer; 11. Support layer. Detailed Embodiments

[0032] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0033] Please refer to Figure 1 , the first aspect embodiment of the present invention provides a pilot-scale device of sulfur autotrophic denitrification filter, including:

[0034] The chemical dosing and water distribution system 1 is used to change the concentration of nitrate in the influent water to conduct nitrate concentration gradient tests to simulate sewage under different water qualities and working conditions, and let the sewage pass through the reactor system, and observe the parameter changes of the sewage after passing through the reactor system to obtain the denitrification effect of the reactor system.

[0035] The reactor system, with its input end connected to the chemical dosing and water distribution system 1, includes a gravity flow reactor 2 and an upflow reactor 3 arranged in parallel. By setting the gravity flow reactor 2 and the upflow reactor 3, when sewage with different water qualities and working conditions passes through, their respective denitrification situations can be obtained, so as to facilitate the selective application of the gravity flow reactor 2 or the upflow reactor 3 under different working conditions, providing accurate reference for subsequent engineering applications.

[0036] Among them, both the gravity flow reactor 2 and the upflow reactor 3 have a filter media layer 10 inside. The filter media layer 10 is sulfur autotrophic denitrification filler. Since sulfur autotrophic denitrification filler does not require an external organic carbon source during application and has a lower backwashing frequency compared to traditional filter media, it can achieve the purpose of reducing sludge production rate and operating cost, and can also effectively improve the denitrification effect. In addition, since the residence time of sewage passing through the sulfur autotrophic denitrification filter is short, the function of high denitrification load can be realized, thereby effectively saving the floor area required for this device and improving space utilization rate.

[0037] A clear water tank 4, which is connected to the output end of the reactor system and is used to receive the clear water after passing through the reactor system.

[0038] A monitoring system 5, which is used to monitor the parameter changes (such as nitrate nitrogen, total nitrogen, pH and other parameters) of the water flow after passing through the gravity flow reactor 2 and the upflow reactor 3, that is, to visually display the denitrification effect of the reactor system.

[0039] A backwashing system 6, which is arranged between the clear water tank 4 and the reactor system and is used to conduct regular water washing, air washing or combined air-water washing on the gravity flow reactor 2 and the upflow reactor 3.

[0040] This device combines the sulfur autotrophic denitrification technology with the existing denitrification deep bed filter technology by setting the chemical dosing and water distribution system 1, the reactor system with a filter media layer 10 formed by sulfur autotrophic denitrification filler, the clear water tank 4 and the monitoring system 5. And by means of the chemical dosing and water distribution system 1, the nitrate concentration in the influent is regulated to simulate the operation under different water qualities and working conditions, so as to obtain the denitrification effects of the gravity flow reactor 2 and the upflow reactor 3 under different water qualities and working conditions, and optimize the design of the reactor system according to the denitrification effects, thus being able to provide accurate reference for subsequent engineering applications.

[0041] Moreover, the backwashing system 6 can be used to backwash the filter media layer in time to remove the intercepted suspended solids and proliferated microorganisms, thereby reducing the head loss.

[0042] Among them, a first backwashing pipeline and a second backwashing pipeline are respectively connected between the clean water tank 4, the gravity flow reactor 2, and the upflow reactor 3, respectively, for backwashing the gravity flow reactor 2 and the upflow reactor 3.

[0043] Specifically, the backwashing system 6 is arranged on the first backwashing pipeline and the second backwashing pipeline, and includes two backwashing water pumps 61 and a backwashing air blower 62, which are used for water washing, air washing or combined water and air washing of the gravity flow reactor 2 and the upflow reactor 3 to improve the backwashing effect.

[0044] It should be noted that the two backwashing water pumps 61 are respectively arranged on the first backwashing pipeline and the second backwashing pipeline, and the backwashing air blower 62 is respectively connected to the first backwashing pipeline and the second backwashing pipeline through pipelines. That is, the first backwashing pipeline and the second backwashing pipeline are connected to the same backwashing air blower 62, reducing the cost required for equipment application.

[0045] In addition, first flow meters 7 are arranged on both the first backwashing pipeline and the second backwashing pipeline for detecting the backwashing water volume.

[0046] In other embodiments, a second flow meter 8 is arranged between the chemical dosing and water distribution system 1 and the reactor system for detecting the water inflow of the gravity flow reactor 2 and the upflow reactor 3, facilitating the operator to control and adjust the water inflow.

[0047] In a further embodiment, triangular weir plates 9 and supporting layers 11 are also respectively provided inside the gravity flow reactor 2 and the upflow reactor 3.

[0048] Among them, the triangular weir plates 9, the filter media layer 10, and the supporting layers 11 are arranged from top to bottom.

[0049] In other embodiments, the thickness of the filter media layer 10 is one-third to one-half of the height of the gravity flow reactor 2 or the upflow reactor 3.

[0050] It should be noted that the monitoring system 5 in this embodiment includes on-line monitoring instruments, and the on-line monitoring instruments are arranged in parallel with the reactor system to respectively monitor the parameter changes of the water flow when passing through the gravity flow reactor 2 and the upflow reactor 3.

[0051] In this embodiment, the following application scenarios are also proposed to simulate the operation conditions of the two reactors under different water qualities and working conditions, so that during engineering applications, the operator can selectively select the gravity flow reactor 2 or the upflow reactor 3 according to the application scenarios, which are specifically as follows:

[0052] The first stage (raw water stage): The influent NO3 - -N concentration in this stage is 2.73 - 5.71 mg / L, and the influent flow rate is controlled at 4 m 3 / h (HRT = 1.0 h); the denitrification load of the upflow reactor 3 is 0.04 - 0.16 kg / m 3 / d, and the denitrification load of the gravity flow reactor 2 is 0.04 - 0.11 kg / m 3 / d; the influent flow rate is controlled at 8 m 3 / h (HRT = 0.5 h), the denitrification load of the upflow reactor 3 is 0.13 - 0.24 kg / m 3 / d, and the denitrification load of the gravity flow reactor 2 is 0.14 - 0.23 kg / m 3 / d. It can be seen that in the raw water stage, the denitrification effects of the two reactors are both significant and there is little difference.

[0053] The second stage (low concentration stage): In this stage, KNO3 is added to the chemical dosing and water distribution system 1 to adjust the influent NO3 - -N concentration. The influent NO3 - -N concentration in this stage is 7.33 - 12.03 mg / L, and the influent flow rate is controlled at 4 m 3 / h (HRT = 1.0 h), the denitrification load of the upflow reactor 3 is 0.15 - 0.27 kg / m 3 / d, and the denitrification load of the gravity flow reactor 2 is 0.14 - 0.24 kg / m 3 / d; the influent flow rate is controlled at 8 m 3 / h (HRT = 0.5 h), the denitrification load of the upflow reactor 3 is 0.33 - 0.57 kg / m 3 / d, and the denitrification load of the gravity flow reactor 2 is 0.31 - 0.55 kg / m 3 / d. It can be seen that in the low concentration stage, the denitrification effects of the two reactors are both significant, and the gravity flow reactor 2 is slightly inferior.

[0054] The third stage (medium concentration stage): In this stage, KNO3 is added to the chemical dosing and water distribution system 1 to adjust the influent NO3 - -N concentration. The influent NO3 - -N concentration in this stage is 15.18 - 20.03 mg / L, and the influent flow rate is controlled at 4 m 3 / h (HRT = 1.0 h), the denitrification load of the upflow reactor 3 is 0.33 - 0.47 kg / m 3 / d, and the denitrification load of the gravity flow reactor 2 is 0.30 - 0.42 kg / m 3 / d; the influent flow rate is controlled at 8 m 3 / h (HRT = 0.5 h), the denitrification load of the upflow reactor 3 is 0.69 - 0.89 kg / m 3 / d, and the denitrification load of the gravity flow reactor 2 is 0.65 - 0.80 kg / m 3 / d. It can be seen that as the influent NO3 - -N concentration increases, the denitrification load of the gravity flow reactor 2 is lower than that of the upflow reactor 3.

[0055] Fourth stage (high concentration stage): In this stage, KNO3 is added to the dosing and water distribution system 1 to adjust the influent NO3 - -N concentration. The influent NO3 - -N concentration in this stage is 20 - 30 mg / L. The influent flow rate is controlled at 4 m 3 / h (HRT = 1.0 h). The denitrification load of the upflow reactor 3 is 0.47 - 0.69 kg / m 3 / d, and the denitrification load of the gravity flow reactor 2 is 0.40 - 0.58 kg / m 3 / d; when the influent flow rate is controlled at 8 m 3 / h (HRT = 0.5 h), the maximum denitrification load of the upflow reactor 3 is 1.38 kg / m 3 / d, and the maximum denitrification load of the gravity flow reactor 2 is 0.98 kg / m 3 / d.

[0056] Fifth stage (ultimate denitrification stage): In this stage, KNO3 is added to the dosing and water distribution system 1 to adjust the influent NO3 - -N concentration. The influent NO3 - -N concentration in this stage is 25 - 30 mg / L. The influent flow rate is controlled at 12 m 3 / h (HRT = 0.34 h). The ultimate denitrification load of the upflow reactor 3 is 1.97 kg / m 3 / d, and the ultimate denitrification load of the gravity flow reactor 2 is 1.03 kg / m 3 / d. It can be seen that as the influent NO3 - -N concentration increases and the influent flow rate increases, the denitrification load of the gravity flow reactor 2 is much lower than that of the upflow reactor 3.

[0057] Therefore, in the working conditions with low requirements for denitrification load, both can be used; in the scenarios with strict requirements for denitrification load, it is recommended to choose the upflow reactor 3.

[0058] In the test stage, the backwashing frequency of the up-flow reactor 3 is once every 7 days, and the backwashing frequency of the gravity-flow reactor 2 is once every 3 days. The backwashing process is air washing for 3 minutes, air-water combined washing for 3 minutes, and water washing for 3 minutes. It can be seen that the backwashing frequency of the up-flow reactor 3 is lower than that of the gravity-flow reactor 2, but both are lower than 2 days per day of the traditional filter. Therefore, by combining the sulfur autotrophic denitrification technology with the existing deep-bed denitrification filter technology, the denitrification effect and rate can be effectively improved.

[0059] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical method of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical method of the present invention.

Claims

1. A sulfur autotrophic denitrification filter pilot plant, characterized in that: include: A dosing and water distribution system (1) for changing the concentration of nitrate in the influent water to conduct a nitrate concentration gradient test; A reactor system, the input end of which is connected to the drug addition and water distribution system (1), comprising a gravity flow reactor (2) and an upflow reactor (3) arranged in parallel; Wherein, the gravity flow reactor (2) and the upward flow reactor (3) both have a filter material layer (10) inside, and the filter material layer (10) is a sulfur autotrophic denitrification filler; A clean water tank (4) connected to the output end of the reactor system; A monitoring system (5) for monitoring parameter changes of water flow after it passes through the gravity flow reactor (2) and the upflow reactor (3); The backwashing system (6) is arranged between the clean water tank (4) and the reactor system, and is used to regularly wash the gravity flow reactor (2) and the upflow reactor (3) with water, air or a combination of air and water.

2. The sulfur autotrophic denitrification filter pilot plant according to claim 1, characterized in that: A first backwashing pipeline and a second backwashing pipeline are respectively connected between the clean water tank (4) and the gravity flow reactor (2) and the upward flow reactor (3); The backwash system (6) is arranged on the first backwash pipeline and the second backwash pipeline, and comprises two backwash water pumps (61) and a backwash fan (62), which are used to perform water washing, air washing or air-water combined washing on the gravity flow reactor (2) and the upflow reactor (3).

3. The sulfur autotrophic denitrification filter pilot plant according to claim 2, characterized in that: The two backwash water pumps (61) are respectively arranged on the first backwash pipeline and the second backwash pipeline; The backwash fan (62) is connected to the first backwash pipeline and the second backwash pipeline through pipelines respectively.

4. The sulfur autotrophic denitrification filter pilot plant according to claim 2, characterized in that: The first backwash pipeline and the second backwash pipeline are both provided with a first flow meter (7) for detecting the backwash water volume.

5. The sulfur autotrophic denitrification filter pilot plant according to any one of claims 1 to 4, characterized in that: A second flow meter (8) is provided between the dosing and water distribution system (1) and the reactor system, and is used to detect the water inflow of the gravity flow reactor (2) and the upward flow reactor (3).

6. The sulfur autotrophic denitrification filter pilot plant according to any one of claims 1 to 4, characterized in that: The gravity flow reactor (2) and the upward flow reactor (3) are both provided with a triangular weir plate (9) and a supporting layer (11); The triangular weir plate (9), the filter material layer (10) and the supporting layer (11) are arranged from top to bottom.

7. The sulfur autotrophic denitrification filter pilot plant according to any one of claims 1 to 4, characterized in that: The thickness of the filter material layer (10) is one third to one half of the height of the gravity flow reactor (2) or the upflow reactor (3).

8. The sulfur autotrophic denitrification filter pilot plant according to any one of claims 1 to 4, characterized in that: The monitoring system (5) comprises an online monitoring instrument.

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