Efficient and energy-saving slaughter wastewater treatment system

Abstract

The utility model discloses an efficient and energy-saving slaughter wastewater treatment system, and belongs to the technical field of sewage treatment. The efficient and energy-saving slaughter wastewater treatment system comprises a water collecting tank, an anaerobic tank, an adjusting tank and a secondary sedimentation tank which are communicated in sequence, a sludge return pipeline communicated with the anaerobic tank is arranged on the regulating tank, and a first aerobic tank and a second aerobic tank which are connected in parallel are arranged between the regulating tank and the secondary sedimentation tank through a pipeline. According to the utility model, the anaerobic tank is adjusted to the front end of the adjusting tank, so that effluent of the water collecting tank firstly enters the anaerobic tank, granular COD (Chemical Oxygen Demand) can be well prevented from being deposited at the bottom of the adjusting tank, a carbon source can be utilized to the greatest extent, the total tank volume is effectively reduced, and the water tank volume and the construction cost are reduced; anaerobic microorganisms in the regulating tank are accumulated and flow back to the anaerobic tank, so that the anaerobic treatment efficiency is greatly improved. According to the utility model, the denitrification efficiency can be effectively improved, the addition of an external carbon source is reduced by reasonably utilizing the own carbon source in the sewage, and the purposes of reducing cost and saving energy are achieved.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, specifically to a high-efficiency and energy-saving slaughterhouse wastewater treatment system. Background Technology

[0002] Slaughter wastewater has a complex composition, mainly containing blood, grease, meat scraps, bone fragments, hair, and feces. It is brownish-red in color and has a strong, foul odor. The wastewater is characterized by large volume, uneven drainage, high concentration, high levels of impurities and suspended solids, and poor biodegradability. The high organic suspended solids content makes it easily perishable, and it also contains a large number of pathogenic microorganisms harmful to human health. Direct discharge into water bodies without treatment would significantly deplete dissolved oxygen, causing serious pollution, damaging ecosystems, and severely impacting human and animal health. The main pollutants in conventional slaughterhouse wastewater are COD, BOD, SS, ammonia nitrogen, total nitrogen, and total phosphorus. Its biggest difference from other high-concentration organic wastewater lies in its high NH3-N concentration, around 120 mg / L. Currently, existing slaughterhouse wastewater treatment devices generally include a collection tank 1, an equalization tank 2, an anaerobic tank 3, an anoxic tank 4, an aerobic tank 5, and a secondary sedimentation tank 6 connected in sequence. The process flow is as follows: Figure 1 As shown. However, the above-described slaughterhouse wastewater treatment device has the following shortcomings: 1. Anaerobic conditions easily occur in the equalization tank, causing excessive COD to be consumed, resulting in insufficient carbon source in the anoxic tank of the denitrification process; 2. The denitrification process relies on the anoxic and aerobic tanks, and the wastewater after aerobic treatment is recycled back to the anoxic tank for further treatment. When the ammonia nitrogen concentration in the influent is high, the recirculation flow rate needs to be increased. On the one hand, this will lead to unstable ammonia nitrogen and total nitrogen levels in the effluent, posing a risk of exceeding the standard. On the other hand, increasing the recirculation will consume more electricity, resulting in higher energy consumption. Utility Model Content

[0003] In order to overcome the shortcomings of the existing technology, the purpose of this utility model is to provide a slaughterhouse wastewater treatment system that can effectively improve denitrification efficiency and reduce the addition of external carbon sources by making reasonable use of the carbon sources in the wastewater, thereby achieving the goal of cost reduction and energy saving.

[0004] To solve the above problems, the technical solution adopted by this utility model is as follows:

[0005] A high-efficiency and energy-saving slaughterhouse wastewater treatment system includes a collection tank, an anaerobic tank, an equalization tank, and a secondary sedimentation tank connected in sequence; the equalization tank is equipped with a sludge return pipeline connected to the anaerobic tank, and a first aerobic tank and a second aerobic tank are connected in parallel through a pipeline between the equalization tank and the secondary sedimentation tank.

[0006] In a preferred embodiment of this utility model, a coarse screen is installed at the front end of the water collection tank.

[0007] More preferably, the coarse grid is a mechanical grid with a grid gap of 5-10 mm.

[0008] In a preferred embodiment of this utility model, a hydraulic screen is provided between the water collection tank and the anaerobic tank.

[0009] In a preferred embodiment of this utility model, the regulating tank is equipped with a lift pump that is connected to the first aerobic tank and the second aerobic tank.

[0010] In a preferred embodiment of this utility model, both the first aerobic tank and the second aerobic tank are equipped with an aeration device and a submersible mixer.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0012] This invention's slaughterhouse wastewater treatment system, on the one hand, adjusts the anaerobic tank to the front of the equalization tank, allowing the effluent from the collection tank to first enter the anaerobic tank. Compared to the existing "equalization tank-anaerobic tank" process, this effectively avoids the deposition of particulate COD at the bottom of the equalization tank, maximizes the utilization of carbon sources, and reduces the total tank volume of the treatment system by about 10%, thus reducing construction costs to some extent. Furthermore, the wastewater after anaerobic treatment contains a small number of anaerobic microorganisms, which are incompatible with aerobic microorganisms. This invention, by setting up an equalization tank after the anaerobic tank, can accumulate anaerobic microorganisms and return them to the anaerobic tank, increasing the biomass of the anaerobic tank and significantly improving anaerobic treatment efficiency. On the other hand, this invention improves the conventional "anoxic tank + aerobic tank" process into two parallel aerobic tanks, which can buffer the system's shock load and reduce the total tank volume by 10% to 30%, saving construction costs while significantly improving denitrification efficiency. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of a slaughterhouse wastewater treatment system in the prior art.

[0014] Figure 2 This is a schematic diagram of the structure of the high-efficiency and energy-saving slaughterhouse wastewater treatment system described in this utility model;

[0015] Figure 3 This is a schematic diagram of the structure of the first and second aerobic tanks described in this utility model;

[0016] The following are the reference numerals: 1. Collection tank; 2. Equalization tank; 3. Anaerobic tank; 4. Anoxic tank; 5. Aerobic tank; 6. Secondary sedimentation tank; 7. Coarse screen; 8. Hydraulic screen; 9. Sludge return pipeline; 10. First aerobic tank; 11. Second aerobic tank; 12. Submersible mixer; 13. Aeration device. Detailed Implementation

[0017] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0018] like Figure 2As shown, the high-efficiency and energy-saving slaughterhouse wastewater treatment system provided by this utility model includes a collection tank 1, an anaerobic tank 3, an equalization tank 2, and a secondary sedimentation tank 6 connected in sequence. A coarse screen 7 is installed at the front end of the collection tank 1, connected to the collection tank 1 via a pipeline. Slaughterhouse wastewater enters the collection tank 1 through the coarse screen 7, which filters the wastewater, intercepting larger diameter impurities and other suspended solids. The filtered wastewater then enters the collection tank 1 for sedimentation, achieving solid-liquid separation through natural sedimentation. Preferably, the coarse screen 7 is a fully stainless steel mechanical screen with a mesh size of 5-10mm. A hydraulic screen 8 is installed between the collection tank 1 and the anaerobic tank 3. After natural sedimentation, the slaughterhouse wastewater in the collection tank 1 is pumped to the hydraulic screen 8 for further removal of impurities such as pig hair. Slaughterhouse wastewater is preferentially fed into anaerobic tank 3 via hydraulic screen 8. Anaerobic tank 3 primarily utilizes anaerobic bacteria to hydrolyze, acidify, and methanate the organic matter in the wastewater, thereby removing organic matter and improving its biodegradability. The anaerobic wastewater contains a small amount of anaerobic microorganisms, which are incompatible with aerobic microorganisms. After anaerobic treatment, the wastewater enters equalization tank 2 through pipelines, where anaerobic microorganisms accumulate. Equalization tank 2 is equipped with a sludge return pipeline 9 connected to anaerobic tank 3. Anaerobic microorganisms are returned to anaerobic tank 3 through sludge return pipeline 9, effectively increasing the biomass in anaerobic tank 3 and significantly improving anaerobic treatment efficiency. Compared to the traditional "equalization tank 2 - anaerobic tank 3" system design, slaughterhouse wastewater first enters the anaerobic tank 3 for anaerobic treatment. This effectively prevents particulate COD from depositing at the bottom of the equalization tank 2, maximizes the utilization of carbon sources, reduces the amount of external carbon sources required, and achieves a certain cost reduction effect. Simultaneously, by placing the anaerobic tank 3 at the front end of the equalization tank 2, the total tank volume can be reduced by approximately 10%, decreasing the water volume and saving on the construction cost of the treatment system. A first aerobic tank 10 and a second aerobic tank 11 are connected in parallel via pipelines between the equalization tank 2 and the secondary sedimentation tank 6. This invention improves the conventional "anoxic tank 4 + aerobic tank 5" process by connecting the first aerobic tank 10 and the second aerobic tank 11 in parallel. The first aerobic tank 10 and the second aerobic tank 11 operate alternately, which can effectively adapt to the system's shock loads, reduce the total tank volume by 10% to 30%, save on construction costs, and significantly improve denitrification efficiency. Furthermore, the equalization tank 2 is equipped with a lift pump connected to the first aerobic tank 10 and the second aerobic tank 11. Based on the COD concentration in the equalization tank 2, the slaughterhouse wastewater in the equalization tank 2 is continuously lifted to the first aerobic tank 10 or the second aerobic tank 11, avoiding waste of carbon sources and reducing the amount of external carbon source added for total nitrogen removal. In some embodiments, such as... Figure 3As shown, both the first aerobic tank 10 and the second aerobic tank 11 are equipped with an aeration device 13 and a submersible mixer 12. During normal operation, the submersible mixer 12 is kept on to ensure that the wastewater in the tank is fully mixed with the nitrifying / denitrifying microbial community. The start-up and shutdown time and operating duration of the aeration device 13 are adjusted according to the detection values ​​of dissolved oxygen, ammonia nitrogen, total nitrogen, and other indicators in the aerobic tank to achieve energy saving. For example, when the ammonia nitrogen concentration in the slaughterhouse wastewater in the treatment system is high, the operating time of the aeration device 13 can be set to be longer to control the dissolved oxygen concentration in the tank at 2.0-4.0 mg / L to remove ammonia nitrogen; when the ammonia nitrogen concentration in the slaughterhouse wastewater in the treatment system is low and the nitrate / nitrite concentration is high, the aeration device 13 can be turned off, and only the submersible mixer 12 can be kept running to remove nitrate / nitrite total nitrogen and achieve stable compliance. After aerobic treatment, the slaughterhouse wastewater enters the secondary sedimentation tank 6 for sedimentation, achieving solid-liquid separation before being discharged in compliance with standards.

[0019] As can be seen from the above scheme, the high-efficiency and energy-saving slaughterhouse wastewater treatment system of this utility model can effectively improve the denitrification efficiency, and the ammonia nitrogen and total nitrogen indicators of the effluent meet the standards more stably. By making reasonable use of the carbon source in the wastewater to reduce the addition of external carbon source, the cost of chemicals is saved, and the purpose of cost reduction and energy saving is achieved. At the same time, it is flexible in operation and can adjust the dissolved oxygen concentration in the aerobic tank by controlling the start and stop of the aeration device, thereby adapting to the system shock caused by changes in the ammonia nitrogen / total nitrogen concentration in the raw water.

[0020] The above embodiments are merely preferred embodiments of this utility model and should not be construed as limiting the scope of protection of this utility model. Any non-substantial changes and substitutions made by those skilled in the art based on this utility model shall fall within the scope of protection claimed by this utility model.

Claims

1. A high efficiency and energy saving system for treating slaughterhouse wastewater, characterized in that: It comprises sequentially connected water collecting pool, anaerobic pool, adjusting pool and secondary sedimentation tank; the adjusting pool is provided with sludge return pipeline communicated with the anaerobic pool, and the adjusting pool and the secondary sedimentation tank are provided with parallel first and second aerobic tanks through pipeline.

2. The high efficiency and energy saving slaughter wastewater treatment system according to claim 1, characterized in that: The front end of the water collecting pool is provided with coarse grid.

3. The high efficiency and energy saving slaughter wastewater treatment system according to claim 2, characterized in that: The coarse grid is mechanical grid, and the grid gap is 5-10 mm.

4. The high efficiency and energy saving slaughter wastewater treatment system according to claim 1, characterized in that: The water collecting pool is provided with hydraulic sieve between the water collecting pool and the anaerobic pool.

5. The high efficiency and energy saving slaughter wastewater treatment system according to claim 1, characterized in that: The adjusting pool is provided with lifting pump.

6. The high efficiency and energy saving slaughter wastewater treatment system according to claim 1, characterized in that: The first and second aerobic tanks are both provided with aeration device and submersible mixer.

Images