An improved autotrophic denitrification nitrogen removal system

Abstract

The utility model discloses an improved autotrophic denitrification system, characterized in that it comprises a primary sedimentation tank, an intermediate pool 1, a coagulation tank, a final sedimentation tank and an effluent monitoring pool connected in sequence, and the intermediate pool 1 and the coagulation tank are connected with the intermediate pool 2, a buffer tank and an autotrophic denitrification filter tank through a three-way joint in sequence, and the autotrophic denitrification filter tank is connected with the coagulation tank. The utility model has the advantages of simple structure and remarkable effect, and solves the problems of effluent whitening, excessive volatile phenol and excessive suspended solids in the autotrophic denitrification system.

Description

Technical Field

[0001] This utility model relates to a wastewater treatment device, specifically an improved autotrophic denitrification system for treating wastewater. Background Technology

[0002] Autotrophic denitrification is a method for treating nitrogen-containing wastewater, primarily using inorganic substances (such as hydrogen and sulfur) as electron donors and inorganic carbon compounds (such as CO2 and HCO3) as fuel. - Sulfur, as a carbon source, releases energy through redox reactions for nitrogen removal. Sulfur autotrophic denitrification is widely used due to its high denitrification efficiency, low sulfur price, readily available raw materials, stable operation, and low sludge production.

[0003] Currently, autotrophic denitrification is frequently used for the treatment of nitrochlorobenzene wastewater. (See attached reference) Figure 1 The typical autotrophic denitrification process for nitrogen-containing wastewater is as follows: nitrogen-containing wastewater, primary sedimentation tank, intermediate tank 1, coagulation tank, final sedimentation tank, intermediate tank 2, buffer tank, autotrophic denitrification filter, effluent monitoring tank, and discharge after reaching standards. After pretreatment, organic nitrogen is converted into nitrate nitrogen, which is then pumped to a nitrate wastewater collection tank and mixed with effluent from the circulating water wastewater treatment system. This maintains the salinity and nitrate nitrogen levels in the water at a suitable level for autotrophic denitrification bacteria reaction. The wastewater then enters the primary sedimentation tank, and subsequently passes through intermediate tank 1, coagulation tank, final sedimentation tank, intermediate tank 2, and buffer tank before being pumped to the autotrophic denitrification filter. The filter is filled with autotrophic denitrification media. Utilizing the electron donors and alkalinity provided by the autotrophic filter media, autotrophic denitrification bacteria attached to and growing on the surface of the media convert nitrate nitrogen into N2, completing the denitrification process. The denitrified wastewater is then pumped to the effluent monitoring tank and discharged after passing monitoring.

[0004] However, when the concentration is reduced to low levels, the water quality is prone to appearing whitish, which is caused by microorganisms or their secretions. Specifically, the influent water does not appear whitish, the whitishness on the filter surface is not obvious, the whitishness in the clear water tank is more pronounced, and white substances adhere to the filter outlet channel, clear water tank, downstream pipes, and tank walls, resulting in whitish effluent. Therefore, existing autotrophic denitrification processes often result in whitish effluent after denitrification, with a high amount of flocculent precipitate, easily leading to excessive levels of total volatile phenols and suspended solids. Summary of the Invention

[0005] The purpose of this invention is to address the problem that the effluent from the above-mentioned autotrophic denitrification process often turns white, with a large amount of flocculent precipitate, which easily leads to excessive levels of total volatile phenols, suspended solids, and other indicators. Therefore, an improved autotrophic denitrification system is proposed.

[0006] The main technical solution of this utility model is: an improved autotrophic denitrification denitrification system, characterized in that it includes a primary sedimentation tank, an intermediate water tank 1, a coagulation tank, a final sedimentation tank, and an effluent monitoring tank connected in sequence. The intermediate water tank 1 is also connected in sequence to an intermediate water tank 2, a buffer tank, and an autotrophic denitrification filter. The autotrophic denitrification filter is connected to the coagulation tank.

[0007] Furthermore, the autotrophic denitrification filter is divided into several small compartments, preferably 8 compartments, each with a volume of less than 100 m³. 3 This ensures that water distribution and backwashing water are carried out evenly.

[0008] Furthermore, the autotrophic denitrification filter is filled with autotrophic denitrification filter media, on which autotrophic denitrifying bacteria are adsorbed. Preferably, the diameter of the autotrophic denitrification filter media is 1~10mm.

[0009] Furthermore, the coagulation tank is equipped with a stirrer and a coagulant feeding port.

[0010] Furthermore, both the primary sedimentation tank and the final sedimentation tank are equipped with scrapers.

[0011] Furthermore, both intermediate water tank 1 and intermediate water tank 2 are equipped with inclined plate sedimentation devices.

[0012] Furthermore, the buffer pool is equipped with an inclined plate settling device.

[0013] This invention adds a connecting pipeline between intermediate water tank 1 and intermediate water tank 2, and adds a pipeline from the effluent pipeline of the autotrophic denitrification filter to the coagulation tank, and adds a pipeline from the final sedimentation tank to the effluent monitoring tank. This is equivalent to adding a sedimentation process after the effluent from the autotrophic denitrification filter. By adjusting the dosage of PAC and PAM in the flocculation tank, the effluent is made clear. The whitish sludge after sedimentation is treated by the sludge treatment equipment in the final sedimentation tank.

[0014] This invention presents an improved autotrophic denitrification system with a simple structure and significant effect. It solves the problem that the effluent from autotrophic denitrification often turns white, contains a large amount of flocculent sediment, and easily causes the total effluent to exceed the standards for volatile phenols, suspended solids, and other indicators. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of an existing autotrophic denitrification system.

[0016] Figure 2 This is a schematic diagram of the improved autotrophic denitrification nitrogen removal system in the embodiment.

[0017] In the diagram, 1—primary sedimentation tank; 2—intermediate water tank 1; 3—coagulation tank; 4—final sedimentation tank; 5—intermediate water tank 2; 6—buffer tank; 7—autotrophic denitrification filter; 8—effluent monitoring tank. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and examples. Example

[0019] A company's nitrochlorobenzene wastewater treatment unit employs an improved autotrophic denitrification system. (See attached reference.) Figure 2 It mainly includes a primary sedimentation tank, intermediate water tank 1, coagulation tank, final sedimentation tank, and effluent monitoring tank that are connected in sequence. Intermediate water tank 1 and coagulation tank are connected in sequence to intermediate water tank 2, buffer tank, and autotrophic denitrification filter via a T-junction. The autotrophic denitrification filter is connected to the coagulation tank.

[0020] In the implementation of this example, the effluent from the primary sedimentation tank is sent to the buffer tank via a tee connecting intermediate tank 1 and intermediate tank 2. The effluent from the autotrophic denitrification filter is sent to the coagulation tank, which is equipped with a stirrer and a coagulant inlet. After adding PAC / PAM, the effluent flows to the final sedimentation tank and finally into the effluent monitoring tank. Intermediate tanks 1, 2, and the buffer tank utilize inclined plate settling tanks. The primary and final sedimentation tanks use a scraper to separate sludge. The autotrophic denitrification filter is divided into sections with a volume less than 100 m³. 3 The filter has 8 compartments, each containing autotrophic denitrification media. Autotrophic denitrification bacteria are adsorbed on the surface of the media. The media has a diameter of 1-10mm and is a highly efficient carrier for microorganisms. As an electron donor, the media will be gradually consumed. Only regular (once a year) replenishment of the media is needed to ensure sufficient biomass and electron donors to maintain the high efficiency of autotrophic denitrification.

[0021] After adopting the improved autotrophic denitrification system from the previous example, the whitening phenomenon in the effluent no longer occurred, ensuring that the volatile phenols and suspended solids in the wastewater consistently met the standards.

[0022] Any aspects not described in this embodiment are techniques well-known in the field.

Claims

1. An improved autotrophic denitrification nitrogen removal system, characterized in that... It includes a primary sedimentation tank, intermediate water tank 1, coagulation tank, final sedimentation tank, and effluent monitoring tank that are connected in sequence; intermediate water tank 1 is also connected in sequence to intermediate water tank 2, buffer tank, and autotrophic denitrification filter, and the autotrophic denitrification filter is connected to the coagulation tank.

2. The improved autotrophic denitrification nitrogen removal system as described in claim 1, characterized in that... The autotrophic denitrification filter is divided into several small compartments.

3. The improved autotrophic denitrification nitrogen removal system as described in claim 2, characterized in that... The autotrophic denitrification filter is divided into 8 small compartments, each with a volume of less than 100 m³. 3 .

4. The improved autotrophic denitrification nitrogen removal system as described in claim 1, 2, or 3, characterized in that... The autotrophic denitrification filter is filled with autotrophic denitrification filter media, and autotrophic denitrifying bacteria are adsorbed on the surface of the autotrophic denitrification filter media.

5. The improved autotrophic denitrification nitrogen removal system as described in claim 4, characterized in that... The diameter of the self-nutritive denitrification filter media is 1~10mm.

6. The improved autotrophic denitrification nitrogen removal system as described in claim 1, characterized in that... The coagulation tank is equipped with a stirrer and a coagulant feeding port.

7. The improved autotrophic denitrification nitrogen removal system as described in claim 1, characterized in that... Both the primary sedimentation tank and the final sedimentation tank are equipped with scrapers.

8. The improved autotrophic denitrification nitrogen removal system as described in claim 1, characterized in that... Both intermediate water tank 1 and intermediate water tank 2 are equipped with inclined plate sedimentation devices.

9. The improved autotrophic denitrification nitrogen removal system as described in claim 1, characterized in that... The buffer pool is equipped with an inclined plate settling device.

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