Advanced treatment system for town sewage

Abstract

The utility model relates to an advanced treatment system for town sewage. Aiming at the problem that the phosphorus removal and total nitrogen reduction effects of a denitrification filter tank or a biological aerated filter tank used for upgrading and reconstruction of a sewage plant at present are not obvious, the utility model provides an advanced treatment system for town sewage. The advanced treatment system comprises a water inlet lifting pump tank, a common filter tank, a nitrification and denitrification biological filter tank, a magnetic flocculation sedimentation tank, a catalytic ozonation tank, a contact disinfection tank and a sludge treatment system, and various treatment units such as the common filter tank, the nitrification and denitrification biological filter tank, the magnetic flocculation sedimentation tank and the catalytic ozonation tank are combined; ammonia nitrogen, total nitrogen, total phosphorus and organic matters in the sewage can be effectively removed, and the effluent quality is ensured to reach the ground surface class III water standard. The device disclosed by the utility model has the advantages of efficient nitrogen and phosphorus removal and stable effluent quality, and meanwhile, the use of the magnetic flocculation sedimentation tank reduces the dosage of chemical agents, reduces the operation cost, reduces the sludge yield and reduces the secondary pollution.

Description

Technical Field

[0001] This utility model relates to the field of environmental protection technology, and in particular to a deep treatment system for urban sewage. Background Technology

[0002] In recent years, the effluent quality of urban wastewater treatment plants has basically reached the Class A standard. However, with the advancement of ecological environment construction, various regions have successively introduced stricter local emission standards, requiring wastewater treatment plants to undergo upgrading and renovation to meet the new standards. Currently, the core processes for urban wastewater treatment mostly employ traditional processes such as the activated sludge process, which cannot meet the upgraded emission standards. Therefore, various renovation methods have been adopted to improve effluent quality.

[0003] Existing upgrades and renovations mainly aim to reduce total nitrogen or ammonia nitrogen, primarily using denitrification filters or aerated biological filters. However, these methods are not very effective in removing phosphorus, and the large amount of dissolved oxygen in the influent leads to poor denitrification, making it difficult for the effluent quality to meet the expected requirements. More investment is needed to ensure that the water quality meets the standards.

[0004] The purpose of this application is to provide a combined sewage treatment system for advanced urban sewage treatment, which can reduce costs and ensure that the ammonia nitrogen and total phosphorus levels in the effluent meet the Class III surface water standards. Summary of the Invention

[0005] (I) Purpose of the utility model

[0006] To address the challenges of wastewater treatment in the prior art, this invention proposes a deep treatment system for urban wastewater. This system utilizes a combination of nitrification / denitrification, magnetic flocculation sedimentation, and ozone catalytic oxidation for nitrogen and phosphorus removal. A conventional filter is installed at the system's front end to reduce dissolved oxygen in the influent. Nitrification / denitrification removes ammonia nitrogen and total nitrogen from the wastewater, while magnetic flocculation removes phosphorus by consolidating tiny flocs in the water. Ozone catalytic oxidation disinfects and sterilizes while removing color, odor, and other organic matter, ensuring stable and compliant effluent discharge.

[0007] (II) Technical Solution

[0008] The advanced treatment system includes an influent lift pump tank, a conventional filter, a nitrification-denitrification biological filter, a magnetic flocculation sedimentation tank, an ozone catalytic oxidation tank, a contact disinfection tank, and a sludge treatment system. The influent lift pump tank is connected to an influent pipe at its front end and to a conventional filter at its rear end. The conventional filter is connected to the nitrification-denitrification biological filter at its rear end. The nitrification-denitrification biological filter includes an anoxic denitrification filter and an aerated nitrification filter. A reflux system is installed at the end of the aerated nitrification filter and connected to the front end of the conventional filter. The nitrification-denitrification biological filter is connected to the magnetic flocculation sedimentation tank at its rear end. The magnetic flocculation sedimentation tank is connected to the ozone catalytic oxidation tank and the sludge treatment system at its rear end. The effluent from the magnetic flocculation sedimentation tank enters the ozone catalytic oxidation tank, and the sludge enters the sludge treatment system and is discharged. The ozone catalytic oxidation tank is connected to the contact disinfection tank at its rear end.

[0009] Preferably, the filter media used in the ordinary filter is quartz sand or ceramsite with a porosity greater than 40%, utilizing microorganisms attached to the pores of the filter media to reduce dissolved oxygen in the influent. The hydraulic retention time of the ordinary filter is 8-10 minutes.

[0010] Preferably, the recirculation system at the end of the aerated nitrification filter includes a recirculation pump installed at the end of the aerated nitrification filter and a pipe connecting to the ordinary filter. Part of the nitrified water is recirculated back to the ordinary filter and then flows into the anoxic denitrification filter to promote the denitrification process and further remove total nitrogen from the wastewater. The internal recirculation pump is a variable frequency pump, and the internal recirculation ratio can be adjusted according to process requirements.

[0011] Preferably, the filter media in the nitrification-denitrification biological filter is spherical lightweight porous biological filter media. The filter media particle size in the anoxic denitrification filter is 4-6 mm, the filter media particle size in the aerated nitrification filter is 3-5 mm, the filter media layer height is greater than 3 m, the hydraulic retention time in the anoxic denitrification filter is greater than 20 min, and the hydraulic retention time in the aerated nitrification filter is 2-3 times that of the anoxic denitrification filter.

[0012] Preferably, the magnetic flocculation sedimentation tank includes a PAC mixing tank, a PAM flocculation tank, an inclined tube sedimentation tank, and magnetic flocculation equipment, wherein the effective water depth of the PAC mixing tank and the PAM flocculation tank is greater than 3 meters.

[0013] This invention combines multiple treatment units, including a conventional filter, a nitrification-denitrification biological filter, a magnetic flocculation sedimentation tank, and an ozone catalytic oxidation tank, to effectively remove ammonia nitrogen, total nitrogen, total phosphorus, and organic matter from wastewater, ensuring that the effluent quality meets the Class III surface water standard. Compared with existing technologies, this invention has the advantages of highly efficient nitrogen and phosphorus removal, stable effluent quality, and the use of a magnetic flocculation sedimentation tank reduces the amount of chemical reagents added, lowers operating costs, reduces sludge production, and reduces secondary pollution. Attached Figure Description

[0014] Figure 1This is a process flow diagram of the present invention.

[0015] Figure 2 This is a schematic diagram of the process of the conventional filter and the nitrification-denitrification biological filter of this utility model. Implementation

[0016] The technical solutions of the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that the described embodiments are merely exemplary and are not intended to limit the scope of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0017] like Figure 1 As shown, the present invention proposes a deep treatment system for urban sewage, the specific steps of which are as follows:

[0018] 1) Domestic sewage is lifted by a booster pump pool to meet the head loss of subsequent structures and balance the burial depth of the structures;

[0019] 2) The effluent from the booster pump pool enters the ordinary filter tank, with a hydraulic retention time of 8 minutes to remove dissolved oxygen from the influent;

[0020] 3) The effluent from the ordinary filter enters the nitrification-denitrification biological filter to remove ammonia nitrogen and total nitrogen, while the phosphorus-removing bacteria in the biological filter absorb total phosphorus.

[0021] 4) The effluent from the nitrification-denitrification biological filter is divided into two parts: one part enters the ordinary filter through the reflux system, and the other part enters the magnetic flocculation sedimentation tank.

[0022] 5) The magnetic flocculation sedimentation tank is equipped with a reagent dosing device to add PAC and PAM, which effectively removes residual TP, SS and some insoluble organic matter from the wastewater.

[0023] 6) The effluent from the magnetic flocculation sedimentation tank enters the ozone catalytic oxidation tank for further decolorization, disinfection, and COD degradation, ensuring that the effluent consistently meets the standards;

[0024] 7) The effluent from ozone catalytic oxidation enters the contact disinfection tank for disinfection, killing harmful pathogenic microorganisms;

[0025] 8) The effluent from the contact disinfection tank meets the discharge standards;

[0026] 9) The remaining sludge from the magnetic flocculation sedimentation tank is discharged into the sludge treatment system for harmless treatment.

[0027] In this embodiment, the filter media used in the ordinary filter bed is clay ceramsite with a particle size of 5-8 mm and a porosity greater than 45%.

[0028] In this embodiment, the filter media in the nitrification-denitrification biological filter is spherical lightweight porous biological filter media. The filter media particle size in the anoxic denitrification filter is 4-6 mm, the filter media particle size in the aerated nitrification filter is 3-5 mm, the filter media layer height is 4 m, the hydraulic retention time in the anoxic denitrification filter is 20-25 min, and the hydraulic retention time in the aerated nitrification filter is 40-50 min.

[0029] like Figure 2 As shown, wastewater enters a nitrification-denitrification biological filter after dissolved oxygen is removed by a conventional filter. The nitrification-denitrification biological filter includes an anoxic denitrification filter and an aerated nitrification filter. The aerated nitrification filter is equipped with an aeration device. Part of the effluent from the aerated nitrification filter is returned to the conventional filter to remove dissolved oxygen, and then enters the anoxic denitrification filter to remove total nitrogen through denitrification. The return ratio can be adjusted according to the actual operating conditions.

[0030] All standard parts used in this utility model can be purchased from the market. Other accessories and pipe fittings can be customized according to the description in the instruction manual. The specific connection methods of each part adopt conventional methods such as bolts and welding that are mature in the existing technology. The machinery, parts and equipment adopt conventional models in the existing technology. The pipe connection adopts conventional connection methods in the existing technology, which will not be described in detail here.

[0031] The above description is merely a preferred embodiment of this utility model and is used only to illustrate or explain the principle of this utility model, without limiting the application form of this utility model. Any modifications, equivalent substitutions, improvements, etc., made according to the technical solution of this utility model should be covered within the protection scope of this utility model.

Claims

1. A system for advanced treatment of municipal wastewater, characterized in that, The water treatment system comprises a water inlet lifting pump pool, a common filter pool, a nitrification and denitrification biological filter pool, a magnetic flocculation sedimentation pool, an ozone catalytic oxidation pool, a contact disinfection pool and a sludge treatment system, the water inlet lifting pump pool is connected with a water inlet pipeline at the front end and connected with the common filter pool at the rear end, the common filter pool is connected with the nitrification and denitrification biological filter pool at the rear end, the nitrification and denitrification biological filter pool comprises an anoxic denitrification filter pool and an aeration nitrification filter pool, the aeration nitrification filter pool is provided with a reflux system at the tail end and connected with the front end of the common filter pool, the nitrification and denitrification biological filter pool is connected with the magnetic flocculation sedimentation pool at the rear end, the magnetic flocculation sedimentation pool is connected with the ozone catalytic oxidation pool and the sludge treatment system at the rear end, the effluent of the magnetic flocculation sedimentation pool enters the ozone catalytic oxidation pool, the sludge enters the sludge treatment system and is discharged, and the ozone catalytic oxidation pool is connected with the contact disinfection pool at the rear end.

2. The system for advanced treatment of municipal wastewater according to claim 1, characterized in that, The filter material used in the common filter pool is quartz sand or ceramic particles with a porosity greater than 40%, and the water residence time of the common filter pool is 8-10 min.

3. The system for advanced treatment of municipal wastewater according to claim 1, characterized in that, The filter material used in the nitrification and denitrification biological filter pool is spherical lightweight porous biological filter material, the particle size of the filter material in the anoxic denitrification filter pool is 4-6 mm, the particle size of the filter material in the aeration nitrification filter pool is 3-5 mm, the height of the filter material layer is greater than 3 m, the hydraulic retention time of the anoxic denitrification filter pool is greater than 20 min, and the hydraulic retention time of the aeration nitrification filter pool is 2-3 times that of the anoxic denitrification filter pool.

4. The system for advanced treatment of municipal wastewater according to claim 1, characterized in that, The magnetic flocculation sedimentation pool comprises a PAC mixing pool, a PAM flocculation pool, an inclined tube sedimentation pool and a magnetic flocculation device, and the effective water depth of the PAC mixing pool and the PAM flocculation pool is greater than 3 m.

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