High-efficiency aquaculture wastewater treatment biochemical system

Abstract

The utility model provides a high-efficiency biochemical system for aquaculture wastewater treatment. An outlet of a UASB (Upflow Anaerobic Sludge Blanket) reaction tank is sequentially connected with a first-stage denitrification tank, a first-stage nitrification tank, a second-stage denitrification tank and a second-stage nitrification tank; the tubular micro-filtration membrane system is connected to an outlet of the secondary nitrification tank; a clear liquid outlet of the tubular micro-filtration membrane system is connected with a water producing tank, a sludge outlet of the tubular micro-filtration membrane system is respectively connected with a drain outlet, a primary denitrification tank and a secondary denitrification tank, a sludge discharge valve is arranged between the sludge outlet and the drain outlet, and reflux valves are arranged between the sludge outlet and the primary denitrification tank as well as between the sludge outlet and the secondary denitrification tank; the aeration system consists of a jet aerator, an air blower and a circulating water pump; the jet aerators are respectively arranged in the primary nitrification tank and the secondary nitrification tank, the air blower is respectively connected with the jet aerators, and the circulating water pump is respectively connected between the jet aerators and the tanks where the jet aerators are located through water pipes. The sludge concentration can be improved, and the treatment capacity is enhanced.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment equipment, specifically to a high-efficiency biochemical system for treating aquaculture wastewater. Background Technology

[0002] Existing biological treatment systems for aquaculture wastewater mostly employ an anaerobic digester + two-stage AO (anaerobic-aggregate) + sedimentation tank process. Because sedimentation tanks are used for solid-liquid separation in the biological treatment tanks, the sludge concentration is reduced, resulting in long retention times, large footprints, and high investment costs. Furthermore, the sludge retention time is affected by the hydraulic retention time; a short sludge age and low sludge concentration are unfavorable for the growth of nitrifying bacteria.

[0003] The treatment effect of sedimentation tanks is difficult to guarantee, and problems such as sludge floating and scum are prone to occur. Moreover, because wastewater contains large molecular organic matter that is difficult to degrade, the wastewater often still fails to meet the standards after two-stage AO and sedimentation treatment, requiring additional advanced treatment processes. Utility Model Content

[0004] The purpose of this invention is to provide a highly efficient biochemical system for treating aquaculture wastewater, thereby increasing sludge concentration and enhancing treatment capacity, addressing the problems existing in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A high-efficiency aquaculture wastewater treatment biochemical system includes a UASB reactor, a primary denitrification tank, a primary nitrification tank, a secondary denitrification tank, a secondary nitrification tank, a tubular microfiltration membrane system, and an aeration system. The outlet of the UASB reactor is sequentially connected to the primary denitrification tank, the primary nitrification tank, the secondary denitrification tank, and the secondary nitrification tank. The tubular microfiltration membrane system is connected to the outlet of the secondary nitrification tank. The clarified liquid outlet of the tubular microfiltration membrane system is connected to a permeate tank, and the sludge outlet of the tubular microfiltration membrane system is connected to a sludge discharge outlet, the primary denitrification tank, and the secondary denitrification tank, respectively. A sludge discharge valve is installed between the sludge outlet and the sludge discharge outlet, and a return valve is installed between the sludge outlet and the primary and secondary denitrification tanks. The aeration system consists of jet aerators, blowers, and circulating water pumps. The jet aerators are installed in the primary and secondary nitrification tanks, respectively, and the blowers are connected to the jet aerators. The circulating water pumps are connected to the jet aerators and their respective tanks via water pipes.

[0007] Furthermore, the primary nitrification tank consists of a first primary nitrification tank and a second primary nitrification tank connected sequentially.

[0008] Furthermore, a bag filter is provided before the inlet of the UASB reactor.

[0009] Furthermore, it also includes a cooling system; the cooling system consists of a heat exchanger, heat exchange tubes, a cooling water pump, and a cooling tower; both ends of the heat exchange tubes are connected to the cooling tower, and a cooling water pump is installed on the heat exchange tubes to circulate the fluid medium; the heat exchanger is thermally connected to the middle of the heat exchange tubes; a return pipe is provided on the first-stage second nitrification tank, which is connected to the first-stage first nitrification tank, and a return water pump is installed on the return pipe to allow wastewater to flow to the first-stage first nitrification tank, and the middle of the return pipe is thermally connected to the heat exchanger.

[0010] Furthermore, sludge concentration meters are installed at the top of the primary denitrification tank, the primary nitrification tank, the secondary denitrification tank, and the secondary nitrification tank.

[0011] This invention relates to a high-efficiency biological treatment system for aquaculture wastewater. It utilizes the latest tubular ultrafiltration membrane technology to replace the traditional sedimentation tank, increasing the sludge concentration of the system from the original 4g / L to 15-20g / L, greatly enhancing the system's treatment capacity, thereby reducing retention time and ultimately reducing project investment and land occupation. It is especially suitable for projects with limited land. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of a high-efficiency aquaculture wastewater treatment biochemical system provided in an embodiment of this utility model. Detailed Implementation

[0013] The technical solution of this utility model will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0014] Example 1

[0015] like Figure 1 As shown, this utility model provides a high-efficiency aquaculture wastewater treatment biochemical system, including a UASB reactor 1, a primary denitrification tank 2, a primary nitrification tank 3, a secondary denitrification tank 4, a secondary nitrification tank 5, a tubular microfiltration membrane system 6, and an aeration system 7. The outlet of the UASB reactor 1 is sequentially connected to the primary denitrification tank 2, the primary nitrification tank 3, the secondary denitrification tank 4, and the secondary nitrification tank 5. The tubular microfiltration membrane system 6 is connected to the outlet of the secondary nitrification tank 5. The clarified liquid outlet of the tubular microfiltration membrane system 6 is connected to a product water tank 8. The sludge outlet is connected to the sewage outlet, the primary denitrification tank 2, and the secondary denitrification tank 4, respectively. A sludge discharge valve 61 is provided between the sludge outlet and the sewage outlet, and a return valve 62 is provided between the sludge outlet and the primary denitrification tank 2 and the secondary denitrification tank 4. The aeration system 7 consists of a jet aerator 71, a blower 72, and a circulating water pump 73. The jet aerator 71 is installed in the primary nitrification tank 3 and the secondary nitrification tank 5, respectively. The blower 72 is connected to the jet aerator 71, respectively. The circulating water pump 73 is connected to the jet aerator 71 and the tanks they are in through water pipes.

[0016] Wastewater first enters UASB reactor 1 for treatment to remove most of the pollutants, then flows by gravity into primary denitrification tank 2. After passing through primary denitrification tank 2, primary nitrification tank 3, secondary denitrification tank 4, and secondary nitrification tank 5, it enters tubular microfiltration membrane system 6 for solid-liquid separation. Subsequently, the clarified liquid enters product water tank 8 and is discharged as needed. Sludge is returned to the preceding primary denitrification tank 2 and secondary denitrification tank 4 via the sludge outlet for recycling. A portion of the sludge is also periodically discharged outside the system through the sludge outlet to maintain the sludge concentration within the system within a reasonable range (15-20 g / L).

[0017] Because the system has a high sludge concentration and high oxygen consumption, ordinary microporous aeration heads cannot achieve effective oxygen supply. This invention uses a jet aerator 71 for aeration, which has the characteristics of high aeration density, anti-scaling, and anti-clogging.

[0018] The specific structure of the tubular microfiltration membrane system 6 is existing technology. It is generally composed of multiple sets of microfiltration membranes forming a tubular component.

[0019] Specifically, the primary nitrification tank 3 consists of a primary first nitrification tank 31 and a primary second nitrification tank 32 connected sequentially.

[0020] Preferably, a bag filter 11 is provided before the inlet of the UASB reactor 1. This is to prevent hard particles from entering the biochemical system and damaging the tubular microfiltration membrane system 6.

[0021] Furthermore, it is also preferred to include a cooling system 9; the cooling system 9 consists of a heat exchanger 91, a heat exchange tube 92, a cooling water pump 93, and a cooling tower 94; both ends of the heat exchange tube 92 are connected to the cooling tower 94 respectively, and the cooling water pump 93 is installed on the heat exchange tube 92 to circulate the fluid medium; the heat exchanger 91 is thermally connected to the middle of the heat exchange tube 92; the first-stage second nitrification tank 32 is provided with a return pipe 95 that connects to the first-stage first nitrification tank 31, and the return pipe 95 is equipped with a return water pump to make the sewage flow to the first-stage first nitrification tank 31, and the middle of the return pipe 95 is thermally connected to the heat exchanger 91.

[0022] Because of the intense biological reaction taking place in the primary nitrification tank 3, the water temperature is relatively high. Therefore, heat exchanger 91 is preferred for cooling. The medium in the heat exchange tube 92 is cooled by cooling tower 94, and then circulated by cooling water pump 93, carrying away the high temperature as it flows through heat exchanger 91. Meanwhile, the wastewater from the primary second nitrification tank 32 flows back to the primary first nitrification tank 31 via return water pump, and its temperature is effectively reduced by passing through heat exchanger 91 along the way. The medium mentioned above is generally tap water.

[0023] Preferably, the top of the primary denitrification tank 2, primary nitrification tank 3, secondary denitrification tank 4, and secondary nitrification tank 5 is equipped with a sludge concentration meter to monitor the sludge concentration and send a feedback signal to the sludge discharge valve 61, so that it can automatically operate and maintain the sludge concentration within the optimal range (15-20 g / L).

[0024] This utility model provides a high-efficiency biological treatment system for aquaculture wastewater. Through a tubular microfiltration membrane system 6, the sludge concentration within the system can be increased, thereby significantly improving sludge treatment capacity and efficiency while reducing the required equipment volume. It completely separates the sludge retention time from the hydraulic retention time, ensuring sludge age and providing favorable conditions for the growth of nitrifying bacteria. Furthermore, the tubular microfiltration membrane system 6 guarantees effective solid-liquid separation, eliminating sludge floating and spillage problems. Wastewater does not require further treatment and can meet discharge standards. The equipment has a high degree of automation, operating automatically, reducing manual labor and saving operating costs.

[0025] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A high-efficiency biochemical system for treating aquaculture wastewater, characterized in that: The system comprises a UASB reaction tank, a first denitrification tank, a first nitrification tank, a second denitrification tank, a second nitrification tank, a tubular microfiltration membrane system and an aeration system; the outlet of the UASB reaction tank is connected to the first denitrification tank, the first nitrification tank, the second denitrification tank and the second nitrification tank in sequence; the tubular microfiltration membrane system is connected to the outlet of the second nitrification tank; the clear liquid outlet of the tubular microfiltration membrane system is connected to a water production tank; the sludge outlet of the tubular microfiltration membrane system is connected to a sewage outlet, the first denitrification tank and the second denitrification tank respectively; a sludge discharge valve is arranged between the sludge outlet and the sewage outlet; and a reflux valve is arranged between the sludge outlet and the first denitrification tank and the second denitrification tank; the aeration system comprises a jet aerator, a blower and a circulating water pump; the jet aerator is arranged in the first nitrification tank and the second nitrification tank respectively; the blower is connected to the jet aerator; and the circulating water pump is connected to the jet aerator and the tank in which the jet aerator is arranged by a water pipe.

2. The high efficiency aquaculture wastewater treatment biochemical system according to claim 1, characterized in that: The first nitrification tank comprises a first first nitrification tank and a first second nitrification tank connected in sequence.

3. The high efficiency aquaculture wastewater treatment biochemical system according to claim 1, characterized in that: A bag filter is arranged in front of the inlet of the UASB reaction tank.

4. The high efficiency aquaculture wastewater treatment biochemical system according to claim 2, characterized in that: The system further comprises a cooling system; the cooling system comprises a heat exchanger, a heat exchange pipe, a cooling water pump and a cooling tower; the two ends of the heat exchange pipe are connected to the cooling tower respectively; the cooling water pump is arranged on the heat exchange pipe to make the fluid medium circulate; the heat exchanger is connected to the middle part of the heat exchange pipe in a heat conduction mode; a reflux pipe is arranged on the first second nitrification tank and connected to the first first nitrification tank; the reflux water pump is arranged on the reflux pipe to make the sewage flow to the first first nitrification tank; and the middle part of the reflux pipe is connected to the heat exchanger in a heat conduction mode.

5. The high-efficiency aquaculture wastewater treatment biochemical system according to claim 1 or 2, characterized in that: The top of each of the first denitrification tank, the first nitrification tank, the second denitrification tank and the second nitrification tank is provided with a sludge concentration meter.

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