Low-carbon sewage treatment system

Abstract

The utility model discloses a low-carbon sewage treatment system. The low-carbon sewage treatment system comprises a water inlet system for conveying sewage, a filler is arranged in each tank, an aeration device is arranged in each tank, and the reaction tanks are used for receiving sewage conveyed by the water inlet system and treating the sewage; the water inlet end of the secondary sedimentation tank is communicated with the water outlet end of the reaction tank, and the secondary sedimentation tank is used for carrying out mud-water separation on the treated water body and returning part of settled sludge to the reaction tank; and the cyclone is communicated with the sludge discharge end of the secondary sedimentation tank and is used for receiving sludge settled in the secondary sedimentation tank, screening and separating the sludge and recycling the sludge to the reaction tank or discharging the sludge. According to the system, the treatment process can be adjusted in time when the quality and quantity of inlet water change, and the running state of the system can be adjusted according to the quantity of sewage and the pollutant concentration; internal reflux is not needed, so that energy consumption is reduced; the sludge can be recycled after being screened, and the activity and the concentration of the sludge in the reaction tank can be adjusted, so that different sewage treatment requirements can be met.

Description

Technical Field

[0001] The utility model relates to a low-carbon sewage treatment system, belonging to the technical field of sewage treatment. Background Art

[0002] With rapid socioeconomic development, the volume of sewage treatment is increasing, and a growing number of sewage treatment equipment are being used. To meet diverse sewage treatment needs, sewage treatment equipment processes often require redesign based on sewage quality. However, once a sewage treatment process is established, changes in sewage quality can be difficult to adapt to, often resulting in fluctuating or exceeding effluent quality standards. Furthermore, current sewage treatment processes primarily rely on biological methods, relying on anaerobic, anoxic, and aerobic microbial reactions to remove organic matter, nitrogen, and phosphorus from various wastewaters. However, traditional nitrification / denitrification wastewater denitrification processes require large internal recirculation flows, resulting in high aeration energy consumption. Furthermore, traditional sewage treatment systems produce large amounts of excess sludge, making it difficult to effectively adjust sludge properties to accommodate changes in sewage quality and quantity. Therefore, addressing the challenges of current sewage treatment processes, reducing repetitive process design in the early stages of sewage treatment, improving the efficiency of sewage treatment equipment, enhancing the stability of sewage treatment systems, and reducing energy consumption during the sewage treatment process are new directions for future sewage treatment development. Utility Model Content

[0003] The purpose of this utility model is to provide a low-carbon sewage treatment system, which can adjust the process of the reaction tank in time when the inlet water quality changes to ensure that the effluent water quality meets the standard. It can adjust the system operation status in time when the sewage volume is small or the pollutant concentration is low to reduce the operating energy consumption; in addition, it does not require internal reflux, saving energy consumption; at the same time, the sludge discharged from the secondary sedimentation tank is reused after screening by the cyclone, and the activity and sludge concentration of the reaction tank sludge can be adjusted to meet different sewage treatment needs.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0005] A low-carbon sewage treatment system, comprising:

[0006] Water inlet system, used to transport sewage;

[0007] Several reaction tanks connected in sequence, each filled with fillers and equipped with aeration devices, are used to receive sewage transported through the water inlet system and treat the sewage;

[0008] The secondary sedimentation tank, whose water inlet is connected to the water outlet of the reaction tank, is used to separate the mud and water after treatment and return part of the settled sludge to the reaction tank;

[0009] The cyclone is connected to the sludge discharge end of the secondary sedimentation tank and is used to receive the sludge settled in the secondary sedimentation tank and screen and separate it before recycling it to the reaction tank or discharging it.

[0010] Preferably, the water inlet system includes a water inlet main pipe and a plurality of water inlet branches, each water inlet branch is connected to a corresponding reaction tank, and a water inlet flow regulating valve is provided on the water inlet branch.

[0011] Preferably, the number of reaction cells is at least 3.

[0012] Preferably, the filling amount of the filler in each reaction cell is 30-60%.

[0013] Preferably, the aeration device includes an aeration tube and an aeration head arranged on the aeration tube, and each aeration tube is connected to an external air supply fan through a pipeline.

[0014] Preferably, a flow propeller is installed in each reaction tank for applying a thrust to make the water flow toward the water inlet of the reaction tank.

[0015] Preferably, a sludge return pump is provided at the bottom of the secondary sedimentation tank, the sludge return pump is connected to the reaction tank and the inlet of the cyclone through a pipeline, and a sludge flow regulating valve is installed on the corresponding pipeline.

[0016] Preferably, the sludge return ratio between the secondary sedimentation tank and the reaction tank is 50-150%.

[0017] Preferably, the top mud discharge port and the bottom mud discharge port of the cyclone are both connected to the reaction tank through pipelines, and an upper outlet sludge recycling valve and a lower outlet sludge recycling valve are respectively provided on the corresponding pipelines.

[0018] Preferably, a sludge discharge pipe is provided at the top sludge discharge port and the bottom sludge discharge port of the cyclone, and an upper outlet sludge discharge valve and a lower outlet sludge discharge valve are provided on the corresponding sludge discharge pipes.

[0019] The beneficial effects of the present invention are:

[0020] 1. The process of the biochemical reaction zone is variable. Therefore, when the influent water quality changes, the process of the reaction pool can be adjusted in time to ensure that the effluent water quality meets the standards.

[0021] 2. When the sewage volume is small or the pollutant concentration is low, the system operation status can be adjusted in time to reduce operating energy consumption;

[0022] 3. No need for internal reflux, saving energy;

[0023] 4. The sludge discharged from the secondary sedimentation tank is screened by a cyclone, which can adjust the activity and sludge concentration of the reaction tank sludge to meet different sewage treatment needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the sewage treatment system.

[0025] The main reference numerals in the figures have the following meanings:

[0026] 1. Water inlet system, 2. Reaction tank, 3. Secondary sedimentation tank, 4. Cyclone, 5. Water inlet main pipe, 6. Water inlet branch pipe, 7. Water inlet flow regulating valve, 8. Filler, 9. Aeration device, 10. Aeration pipe, 11. Aeration head, 12. Fan, 13. Flow pusher, 14. Sludge return pump, 15. Sludge flow regulating valve, 16. Upper outlet sludge reuse valve, 17. Lower outlet sludge reuse valve, 18. Upper outlet sludge discharge valve, 19. Lower outlet sludge discharge valve. DETAILED DESCRIPTION

[0027] The low-carbon wastewater treatment systems used in the following embodiments all include a water inlet system 1 , a plurality of reaction tanks 2 , a secondary sedimentation tank 3 and a cyclone 4 .

[0028] The water inlet system 1 is used to transport sewage, and includes a main water inlet pipe 5 and several water inlet branches 6. Each water inlet branch 6 is connected to a corresponding reaction tank 2, and a water inlet flow regulating valve 7 is provided on the water inlet branch 6.

[0029] Several reaction tanks 2 are connected in sequence, each of which is filled with fillers 8 and provided with an aeration device 9 for receiving sewage transported through the water inlet system 1 and treating the sewage.

[0030] The filler 8 is a MBBR suspended filler 8, using a conventional MBBR carrier with a diameter of 25 cm, 19 to 39 pores, and a thickness of 1 cm. The filler 8 content in each reaction tank 2 is 30-60%. The aeration device 9 includes an aeration tube 10 and an aeration head 11 mounted on the aeration tube 10. Each aeration tube 10 is connected to an external air blower 12 via a pipe. Furthermore, a flow propeller 13 is installed in each reaction tank 2 to apply thrust to direct the water toward the inlet of the reaction tank 2.

[0031] The reaction tank 2 has two states. When the aeration is turned on and the flow pusher 13 is turned off, the reaction tank 2 is an aerobic tank and performs an aerobic reaction. When the aeration system is turned off and the flow pusher 13 is turned on, the reaction tank 2 is an anaerobic tank or an anoxic tank and performs an anaerobic or anoxic reaction. Therefore, the reaction tank 2 (1 to n) can be used for both anaerobic / anoxic reactions and aerobic reactions.

[0032] The water inlet end of the secondary sedimentation tank 3 is communicated with the water outlet end of the reaction tank 2, and is used for separating sludge and water after treatment. The bottom of the secondary sedimentation tank 3 is provided with a sludge backflow pump 14, which is communicated with the reaction tank 2 and the inlet of the cyclone 4 through pipelines, and a sludge flow regulating valve 15 is installed on the corresponding pipeline. The water after sludge-water separation is discharged to the next treatment process, part of the settled sludge is backflowed to the reaction tank 2, and the remaining sludge is discharged to the cyclone 4. The sludge backflow ratio between the secondary sedimentation tank 3 and the reaction tank 2 is 50-100%.

[0033] The cyclone 4 is communicated with the sludge discharge end of the secondary sedimentation tank 3, the top sludge discharge port (upper outlet) and the bottom sludge discharge port (lower outlet) are both communicated with the reaction tank 2 through pipelines, and the upper outlet sludge recycling valve 16 and the lower outlet sludge recycling valve 17 are respectively arranged on the corresponding pipelines. The top sludge discharge port and the bottom sludge discharge port of the cyclone 4 are also respectively provided with sludge discharge pipes, and the upper outlet sludge discharge valve 18 and the lower outlet sludge discharge valve 19 are respectively arranged on the corresponding sludge discharge pipes. The cyclone 4 is used for receiving the settled sludge in the secondary sedimentation tank 3 and performing centrifugal separation, and then recycling to the reaction tank 2 or discharging.

[0034] Example 1

[0035] The number of the reaction tank 2 of the sewage treatment system is 5, and has the following four working states:

[0036] Process state 1: 1#, 2#, 3#, 4# and 5# reaction tanks 2 are opened to the aeration device 9 and closed to the pusher 13, and the reaction tanks 2 are all aerobic tanks, and the sewage treatment system is an aerobic process; it can be used for sewage treatment containing only COD.

[0037] Process state 2: 1# and 2# reaction tanks 2 are opened to the pusher 13 and closed to the aeration device 9, which are anoxic tanks; 3#, 4# and 5# reaction tanks 2 are opened to the aeration device 9 and closed to the pusher 13, which are aerobic tanks, and the sewage treatment system is an AO process, which can be used for sewage treatment containing COD and ammonia nitrogen.

[0038] Process state 3: 1#, 2# and 3# reaction tanks 2 are opened to the pusher 13 and closed to the aeration device 9, 1# reaction tank 2 is an anaerobic tank, and 2# and 3# reaction tanks 2 are anoxic tanks; 4# and 5# reaction tanks 2 are opened to the aeration device 9 and closed to the pusher 13, which are aerobic tanks, and the sewage treatment system is an A2O process, which can be used for sewage treatment containing COD, ammonia nitrogen and total phosphorus.

[0039] Process state 4: The flow pushers 13 of 1#, 2# and 4# reaction tanks 2 are turned on, and the aeration device 9 is turned off. The 1# reaction tank 2 is an anaerobic tank, and the 2# and 4# reaction tanks 2 are anoxic tanks; the aeration device 9 of 3# and 5# reaction tanks 2 are turned on, and the flow pushers 13 are turned off, and they are aerobic tanks. The sewage treatment system adopts the AAOAO process, which can be used for sewage treatment with high total nitrogen content.

[0040] Sewage enters the anaerobic / anoxic reaction tanks 2 through the inlet branch pipe 6, flows through each reaction tank 2 in sequence, and then enters the secondary sedimentation tank 3 for sludge-water separation. After sedimentation, the water flows out and enters the next treatment process. Part of the sludge settled in the secondary sedimentation tank 3 is returned to the anaerobic tank through the sludge return pipe, and part enters the cyclone 4. The sludge is centrifugally screened and separated in the cyclone 4, with a portion of the sludge containing more organic matter discharged from the top sludge outlet and a portion of the sludge containing more inorganic matter discharged from the bottom sludge outlet. When the sludge settling performance of the reaction tank 2 needs to be improved, the sludge discharged from the bottom sludge outlet of the cyclone 4 is returned to the reaction tank 2, and the sludge discharged from the top sludge outlet is discharged through the sludge external discharge pipe. When the sludge inorganic content of the sludge needs to be reduced and the sludge activity needs to be increased, the sludge discharged from the top sludge outlet of the cyclone 4 is returned to the reaction tank 2, and the sludge discharged from the bottom sludge outlet is discharged through the sludge external discharge pipe.

[0041] Example 2

[0042] The sewage is a domestic sewage with COD of 200-300 mg / L, ammonia nitrogen of 10-20 mg / L, total phosphorus of 2-3 mg / L, and total nitrogen of 20-30 mg / L. The sewage treatment system has 6 reaction tanks 2, each with an effective volume of 3m3, an MBBR carrier filling volume of 30%, and a sludge return volume of 100%. When the influent is less than 1m 3 / h, when the water volume is small, the process state of reaction tank 2 is AOAAAO, and sewage enters from reaction tanks 21 and 3. At this time, the system can reduce aeration energy consumption as much as possible while meeting the sewage treatment needs; when the water volume is 1-1.5m 3 / h, the process state of reaction tank 2 is adjusted to AOAOAO, which can enhance the efficiency of denitrification treatment in the sewage treatment system; when the water volume is 1.5-2.5m 3 / h, the process state of the reaction tank 2 is AOAOAO. The sludge concentration in the reaction tank 2 can be increased by opening the cyclone 4 to reuse the sludge discharged from the bottom sludge outlet to increase the sewage treatment load of the system.

[0043] Example 3

[0044] The wastewater is from a specific industry, with COD levels of 500-1000 mg / L, ammonia nitrogen levels of 5-10 mg / L, and total nitrogen levels of 10-15 mg / L. The wastewater treatment system has three reactors (2), operating in the AOO process. When the wastewater quality changes to COD levels of 500-1000 mg / L, ammonia nitrogen levels of 10-20 mg / L, and total nitrogen levels of 15-20 mg / L, and the AOA process in reactor 2, cyclone 4 is activated to reuse sludge discharged from the bottom sludge outlet, raising the sludge concentration in reactor 2. This increases the system's wastewater treatment capacity and strengthens the need for denitrification.

[0045] Example 4

[0046] The sewage is from an industrial wastewater. The sewage treatment system was impacted, the sludge was partially disintegrated, and the ammonia nitrogen content in the effluent increased. The cyclone 4 was opened and the sludge flowing out of the top sludge outlet was reused to degrade the inorganic content of the sludge. The content of organic bacterial components such as COD-degrading bacteria and nitrifying bacteria in the sludge in the reaction tank 2 was increased to improve the sludge activity of the system and strengthen the denitrification demand of the sewage.

[0047] The above is only a preferred embodiment of the present utility model patent. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present utility model patent. These improvements and modifications should also be regarded as the scope of protection of the present utility model patent.

Claims

1. A low-carbon sewage treatment system, characterized in that: include: Water inlet system, used to transport sewage; Several reaction tanks connected in sequence, each filled with fillers and equipped with aeration devices, are used to receive sewage transported through the water inlet system and treat the sewage; The secondary sedimentation tank, whose water inlet is connected to the water outlet of the reaction tank, is used to separate the mud and water after treatment and return part of the settled sludge to the reaction tank; The cyclone is connected to the sludge discharge end of the secondary sedimentation tank and is used to receive the sludge settled in the secondary sedimentation tank and screen and separate it before recycling it to the reaction tank or discharging it.

2. The low-carbon sewage treatment system according to claim 1, characterized in that: The water inlet system includes a water inlet main pipe and several water inlet branch pipes. Each water inlet branch pipe is connected to a corresponding reaction tank, and a water inlet flow regulating valve is provided on the water inlet branch pipe.

3. The low-carbon sewage treatment system according to claim 1, characterized in that: The number of reaction cells is at least 3.

4. The low-carbon sewage treatment system according to claim 1, characterized in that: The aeration device includes an aeration tube and an aeration head arranged on the aeration tube. Each aeration tube is connected to an external air supply fan through a pipeline.

5. The low-carbon sewage treatment system according to claim 1, characterized in that: A flow propeller is installed in each reaction tank to apply thrust to make the water flow toward the water inlet of the reaction tank.

6. The low-carbon sewage treatment system according to claim 1, characterized in that: A sludge return pump is provided at the bottom of the secondary sedimentation tank, which is connected to the reaction tank and the inlet of the cyclone through a pipeline, and a sludge flow regulating valve is installed on the corresponding pipeline.

7. The low-carbon sewage treatment system according to claim 1, characterized in that: The top and bottom mud discharge ports of the cyclone are connected to the reaction tank through pipelines, and the upper outlet sludge recycling valve and the lower outlet sludge recycling valve are respectively provided on the corresponding pipelines.

8. The low-carbon sewage treatment system according to claim 7, characterized in that: The top and bottom mud discharge ports of the cyclone are respectively provided with sludge discharge pipes, and the upper and lower outlet sludge discharge valves are respectively provided on the corresponding sludge discharge pipes.

Images