Breeding wastewater pretreatment filtering device and filtering method

Abstract

The invention discloses a culture wastewater pretreatment filtering device and a filtering method, and relates to the technical field of water treatment. The filtering device comprises a screen container, a shell, a stirring system and a back-flushing air connector. The screen container is used for filtering breeding wastewater and intercepting solid residues inside. The shell is arranged on the outer side of the screen container in a sleeving mode and fixedly connected with the screen container. The shell is provided with a water inlet, an in-sieve slag discharging opening and a water outlet. And the water inlet is used for introducing breeding wastewater into the screen container. And the in-screen slag discharge port is communicated with the bottom of the screen container and is used for discharging solid slag in the screen container. The water outlet is used for discharging the filtered breeding wastewater. And the stirring system extends into the screen container and is used for stirring the solid residues in the screen container. The back flushing air connector is fixed to the shell, faces the screen container and is used for cleaning meshes of the screen container. Compared with the prior art, the aquaculture wastewater pretreatment filtering device and the filtering method can improve the removal precision of solid residues in wastewater and realize automatic cleaning.

Description

Technical Field

[0001] The invention relates to the technical field of water treatment, and in particular to a pre-treatment filtering device and a filtering method for aquaculture wastewater. Background Art

[0002] Aquaculture wastewater is one of the important sources of agricultural non-point source pollution in my country. The wastewater contains a high amount of slag, especially some aquaculture wastewater uses the water-soaked manure process, which leads to a significant increase in the solid slag content in the wastewater, mainly including large particle fibers, animal hair and other solid particles. Aquaculture wastewater usually needs to be discharged or used as an agricultural resource after biochemical treatment to meet the standards, but the high solid slag content will cause a series of problems such as pipeline blockage in the subsequent biochemical treatment process. In order to ensure the stable operation of the subsequent treatment system, the aquaculture wastewater needs to be pre-treated and slag removed.

[0003] At present, the pretreatment of aquaculture wastewater is mainly carried out through solid-liquid separation by screens, flat hydraulic screens or spiral solid-liquid separators, but there are still some problems in the implementation process. The filtration accuracy of screens and spiral solid-liquid separators is relatively low, and the residue content in the treated wastewater is still high; while the hydraulic screen relies entirely on gravity for screening. Although the processing accuracy is high, its processing efficiency is low and it is difficult to clean. Summary of the invention

[0004] The purpose of the present invention is to provide a pre-treatment filtering device and a filtering method for aquaculture wastewater, so as to improve the removal accuracy of solid residues in wastewater and realize automatic cleaning.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The invention discloses a pretreatment filtering device for aquaculture wastewater, comprising:

[0007] A screen container for filtering aquaculture wastewater and trapping solid residues;

[0008] The shell is sleeved on the outside of the mesh container and fixedly connected to the mesh container; the shell is provided with a water inlet, a sieve inner residue discharge port and a water outlet; the water inlet is used to introduce aquaculture wastewater into the mesh container; the sieve inner residue discharge port is connected to the bottom of the mesh container and is used to discharge the solid residue in the mesh container; the water outlet is used to discharge the filtered aquaculture wastewater;

[0009] A stirring system extends into the mesh container and is used to stir the solid slag in the mesh container;

[0010] A recoil gas connector is fixed on the shell and faces the screen container, and is used for cleaning the mesh of the screen container.

[0011] Preferably, the lower portion of the screen container has a closing section, and the cross-sectional area of ​​the closing section gradually decreases from top to bottom.

[0012] Preferably, the upper end of the screen container is fixedly connected to the shell via a screen upper support, and the screen upper support closes the gap between the upper end of the screen container and the shell.

[0013] Preferably, the shell is further provided with an external slag discharge port, which is connected to the bottom of the shell and is used to discharge the solid slag in the shell; the water outlet is higher than the external slag discharge port.

[0014] Preferably, slag discharge valves are installed on both the slag discharge port inside the sieve and the slag discharge port outside the sieve.

[0015] Preferably, it also includes a slag discharge main pipe, and the slag discharge port inside the screen and the slag discharge port outside the screen are both connected to the slag discharge main pipe.

[0016] Preferably, the stirring system includes a rotating shaft, a scraper support and a screen scraper; the rotating shaft is located at the center of the screen container, and the scraper support is respectively connected to the rotating shaft and the screen scraper to drive the screen scraper to rotate through the rotating shaft; the screen scraper is used to scrape off the solid slag attached to the screen container.

[0017] Preferably, the stirring system further comprises a slag conveying screw, which is connected to the rotating shaft and is used for pushing the solid slag downward when the rotating shaft rotates.

[0018] Preferably, it further comprises a pressure gauge and an exhaust port, wherein the pressure gauge and the exhaust port are installed on the top of the shell.

[0019] The present invention also discloses a method for pre-treating and filtering aquaculture wastewater, using the aquaculture wastewater pre-treating and filtering device, comprising the following steps:

[0020] Step 1: The aquaculture wastewater to be treated is sent into the screen container from the water inlet, and the solid residue is trapped in the screen container and discharged through the slag discharge port inside the screen; the filtered aquaculture wastewater enters the shell set outside the screen container, the solid residue is discharged through the slag discharge port outside the screen, and the aquaculture wastewater is discharged from the water outlet;

[0021] Step 2: After the pressure in the shell rises to a preset upper limit, stop conveying the aquaculture wastewater to the screen container, start the stirring system, and rotate the screen scraper to clean the solid residue attached to the inner wall of the screen container;

[0022] Step 3: Start the backwash system to backwash the screen container with high-pressure air to blow the solid slag embedded in the mesh away from the mesh.

[0023] Compared with the related art, the present invention has achieved the following technical effects:

[0024] The present invention improves the solid residue filtering accuracy by using a screen container, and improves the fluidity of the solid residue in the screen container by a stirring system, thereby improving the solid residue discharge efficiency; a jet airflow is provided by a recoil gas joint to blow away the solid residue embedded in the mesh of the screen container, thereby realizing automatic cleaning of the screen container without stopping the machine. The stirring system is used in combination with the recoil gas joint, so that the screen container always maintains a high aquaculture wastewater filtering capacity, thereby improving the aquaculture wastewater treatment efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 This is a schematic diagram of a pre-treatment filtering device for aquaculture wastewater according to an embodiment of the present invention;

[0027] Figure 2 for Figure 1 Top schematic diagram of the structure in Figure 2.

[0028] In the figure: 1- stirring motor; 2- pressure gauge; 3- quick-release bolt; 4- water inlet; 5- shell; 6- scraper support; 7- recoil gas joint; 8- slag discharge main pipe; 9- slag discharge port inside the screen; 10- slag discharge port outside the screen; 11- support foot; 12- slag discharge valve; 13- slag conveying screw; 14- water outlet; 15- screen scraper; 16- screen container; 17- support on the screen; 18- bolt; 19- sealing cover plate; 20- exhaust port; 21- rotating shaft. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] The purpose of the present invention is to provide a pre-treatment filtering device and a filtering method for aquaculture wastewater, so as to improve the removal accuracy of solid residues in wastewater and realize automatic cleaning.

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Reference Figure 1 , Figure 2 This embodiment provides a breeding wastewater pretreatment filtering device, including a screen container 16, a shell 5, a stirring system and a backwash gas connector 7.

[0033] The screen container 16 is used to filter the aquaculture wastewater and trap the solid residue inside. The shell 5 is sleeved on the outside of the screen container 16 and fixedly connected to the screen container 16. The shell 5 is provided with a water inlet 4, a sieve residue discharge port 9 and a water outlet 14. The water inlet 4 is used to introduce aquaculture wastewater into the screen container 16. The sieve residue discharge port 9 is connected to the bottom of the screen container 16 and is used to discharge the solid residue in the screen container 16. The water outlet 14 is used to discharge the filtered aquaculture wastewater. The stirring system extends into the screen container 16 and is used to stir the solid residue in the screen container 16. The recoil gas joint 7 is fixed on the shell 5 and faces the screen container 16, and is used to clean the mesh of the screen container 16.

[0034] The working principle of the aquaculture wastewater pretreatment filtration device in this embodiment is as follows:

[0035] In this embodiment, while using the screen container 16 to improve the solid residue filtering accuracy, the stirring system is used to improve the fluidity of the solid residue in the screen container 16, thereby improving the solid residue discharge efficiency; the jet airflow is provided by the recoil gas joint 7 to blow away the solid residue embedded in the mesh of the screen container 16, thereby realizing automatic cleaning of the screen container 16 without stopping the machine. The stirring system is used in combination with the recoil gas joint 7, so that the screen container 16 always maintains a high aquaculture wastewater filtering capacity, thereby improving the aquaculture wastewater treatment efficiency.

[0036] Exemplarily, there are multiple backwash gas connectors 7, which are evenly distributed along the circumferential direction of the housing 5, so that the side of the screen container 16 in the entire circumferential direction is backwashed. In the height direction of the housing 5, the backwash gas connector 7 is only arranged in the height range corresponding to the screen container 16.

[0037] As a possible example, in this embodiment, the lower part of the screen container 16 has a closing section, and the cross-sectional area of ​​the closing section gradually decreases from top to bottom. The closing section gathers the solid slag in the screen container 16, so that the solid slag flows downward and gathers near the slag discharge port 9 in the screen, so as to facilitate the rapid discharge of the solid slag.

[0038] As a possible example, in this embodiment, the upper end of the screen container 16 is fixedly connected to the housing 5 via a screen support 17, and the screen support 17 closes the gap between the upper end of the screen container 16 and the housing 5. The screen support 17 can be fixed using bolts 18.

[0039] When the recoil gas connector 7 sprays gas into the shell 5, due to the obstruction of the support 17 on the screen, the airflow will not flow out upward through the gap between the screen container 16 and the shell 5, but can only enter the screen container 16 through the mesh holes of the screen container 16, so that more airflow can clean the solid slag embedded in the mesh holes, thereby improving the utilization rate of the airflow.

[0040] When the aquaculture wastewater enters the shell 5 through the water inlet 4, due to the obstruction of the support 17 on the screen, the aquaculture wastewater will not flow directly downward to the gap between the screen container 16 and the shell 5, but will first flow into the screen container 16, and then enter the gap between the screen container 16 and the shell 5 after being filtered by the screen container 16.

[0041] When the stirring system stirs the solid slag in the mesh container 16, the mesh container 16 will also be pushed by the solid slag. Since the support 17 on the mesh fills the gap between the upper end of the mesh container 16 and the shell 5, the distance between the mesh container 16 and the shell 5 can be maintained, and the mesh container 16 is prevented from colliding with the shell 5 under the push of the solid slag inside.

[0042] As a possible example, in this embodiment, an external slag discharge port 10 is also provided on the shell 5, and the external slag discharge port 10 is connected to the bottom of the shell 5, and is used to discharge the solid slag in the shell 5 (that is, in the gap between the screen container 16 and the shell 5); the water outlet 14 is higher than the external slag discharge port 10.

[0043] After the solid residue in the gap between the screen container 16 and the shell 5 is gradually precipitated, it can be discharged from the screen external residue discharge port 10, and the upper clarified liquid is discharged from the water outlet 14, thereby performing secondary cleaning of the solid residue in the aquaculture wastewater and further improving the filtering effect of the aquaculture wastewater.

[0044] Exemplarily, the slag discharge port 10 outside the screen is located on the lower surface of the shell 5 , the water inlet 4 and the water outlet 14 are located on the side of the shell 5 , and the water inlet 4 is located above the screen container 16 .

[0045] Exemplarily, the upper surface of the housing 5 is a sealing cover plate 19 detachably fixed by quick-release bolts 183 , so that the internal structure can be easily maintained after the sealing cover plate 19 is removed.

[0046] Exemplarily, a plurality of supporting legs 11 are fixedly connected to the lower surface of the shell 5 , so that the lower surface of the shell 5 is at a certain distance from the ground, providing installation space for the inner sieve slag discharge port 9 , the outer sieve slag discharge port 10 and the slag discharge main pipe 8 .

[0047] As a possible example, in this embodiment, both the slag discharge port 9 inside the screen and the slag discharge port 10 outside the screen are equipped with slag discharge valves 12. By controlling the opening and closing of the slag discharge valves 12, the discharge rhythm of the solid slag can be adjusted.

[0048] As a possible example, in this embodiment, the aquaculture wastewater pretreatment and filtration device further includes a slag discharge main pipe 8, and the slag discharge port 9 inside the screen and the slag discharge port 10 outside the screen are both connected to the slag discharge main pipe 8. The solid slag in the slag discharge port 9 inside the screen and the slag discharge port 10 outside the screen are collected in the slag discharge main pipe 8 and then discharged together.

[0049] As a possible example, in this embodiment, the stirring system includes a rotating shaft 21, a scraper support 6 and a screen scraper 15. The rotating shaft 21 is located at the center of the screen container 16, and the scraper support 6 is respectively connected to the rotating shaft 21 and the screen scraper 15 to drive the screen scraper 15 to rotate through the rotating shaft 21. The screen scraper 15 is used to scrape off the solid slag attached to the screen container 16.

[0050] On the one hand, the screen scraper 15 can improve the fluidity of the solid slag in the screen container 16, making the solid slag looser and preventing the solid slag from solidifying into blocks, so that the solid slag can gradually flow downward to the slag discharge port 9 in the screen; on the other hand, the screen scraper 15 can regularly clean the solid slag layer attached to the inner surface of the screen container 16 to prevent the solid slag from solidifying into blocks on the screen container 16 due to long-term contact with the screen container 16, thereby reducing the difficulty of cleaning the recoil gas joint 7.

[0051] Exemplarily, the screen scraper 15 is an arc-shaped plate, whose shape is consistent with the partial side wall of the cylindrical shell, and the bending direction is toward the rotating shaft 21. When the rotating shaft 21 drives the screen scraper 15 to rotate, the solid slag attached to the screen container 16 slides along the cylindrical surface of the screen scraper 15 close to the rotating shaft 21, and the screen scraper 15 is used as a shovel to separate the solid slag from the screen container 16.

[0052] Exemplarily, the stirring system further includes a stirring motor 1, which is fixed on the sealing cover plate 19 and is in driving connection with the rotating shaft 21 to drive the rotating shaft 21 to rotate. It is understandable that the rotating shaft 21 may also be driven in other ways.

[0053] As a possible example, in this embodiment, the stirring system further includes a slag conveying screw 13, which is connected to the rotating shaft 21 and is used to push the solid slag downward when the rotating shaft 21 rotates. The slag conveying screw 13 not only provides a thrust for the solid slag to flow downward along its own axial direction, but also provides a thrust for the solid slag to flow in a circumferential direction, thereby improving the fluidity of the solid slag, making the solid slag looser, and avoiding agglomeration of the solid slag.

[0054] Exemplarily, the slag discharge port 9 in the screen is located directly below the slag conveying screw 13 and at the center of the closing section of the screen container 16, thereby reducing the flow distance of the solid slag in the screen container 16 and making it easier for the solid slag to be discharged from the screen container 16.

[0055] As a possible example, in this embodiment, the aquaculture wastewater pretreatment filtering device further includes a pressure gauge 2 and an exhaust port 20 , and the pressure gauge 2 and the exhaust port 20 are installed on the top of the shell 5 .

[0056] With the accumulation of solid slag and the jet of the recoil gas connector 7, the pressure in the shell 5 will increase. When the pressure gauge 2 detects that the pressure in the shell 5 increases to a preset pressure threshold, the exhaust port 20 can be opened to reduce the pressure in the shell 5. The exhaust port 20 can also be opened before the recoil gas connector 7 jets, so that the internal and external pressure difference of the recoil gas connector 7 is larger, thereby improving the cleaning effect of the airflow on the solid slag.

[0057] Exemplarily, the pressure gauge 2 and the exhaust port 20 are both mounted on the sealing cover plate 19 .

[0058] This embodiment also provides a method for pre-treatment and filtration of aquaculture wastewater, using the above-mentioned aquaculture wastewater pre-treatment and filtration device, comprising the following steps:

[0059] Step 1: The aquaculture wastewater to be treated is sent into the screen container 16 from the water inlet 4, and the solid residue is trapped in the screen container 16 and discharged through the screen inner residue discharge port 9. The filtered aquaculture wastewater enters the shell 5 set outside the screen container 16, and the solid residue is discharged through the screen outer residue discharge port 10, and the aquaculture wastewater is discharged from the water outlet 14.

[0060] Step 2: After the pressure in the shell 5 rises to a preset upper limit, stop conveying the aquaculture wastewater to the screen container 16 , start the stirring system, and rotate the screen scraper 15 to clean the solid residue attached to the inner wall of the screen container 16 .

[0061] Step 3: Start the backwash system to backwash the screen container 16 with high-pressure air to blow the solid slag embedded in the mesh away from the mesh.

[0062] Since the aquaculture wastewater pretreatment and filtration method uses the above-mentioned aquaculture wastewater pretreatment and filtration device, it also has the corresponding advantages of the aquaculture wastewater pretreatment and filtration device, which will not be described in detail here.

[0063] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A pretreatment filtration device for aquaculture wastewater, characterized in that: include: A screen container for filtering aquaculture wastewater and trapping solid residues; The shell is sleeved on the outside of the mesh container and fixedly connected to the mesh container; the shell is provided with a water inlet, a sieve inner residue discharge port and a water outlet; the water inlet is used to introduce aquaculture wastewater into the mesh container; the sieve inner residue discharge port is connected to the bottom of the mesh container and is used to discharge the solid residue in the mesh container; the water outlet is used to discharge the filtered aquaculture wastewater; A stirring system extends into the mesh container and is used to stir the solid slag in the mesh container; A recoil gas connector is fixed on the shell and faces the screen container, and is used for cleaning the mesh of the screen container.

2. The aquaculture wastewater pretreatment filtering device according to claim 1, characterized in that: The lower part of the screen container has a closing section, and the cross-sectional area of ​​the closing section gradually decreases from top to bottom.

3. The aquaculture wastewater pretreatment filtration device according to claim 1, characterized in that: The upper end of the screen container is fixedly connected to the shell through a support on the screen, and the support on the screen closes the gap between the upper end of the screen container and the shell.

4. The aquaculture wastewater pretreatment filtration device according to claim 1, characterized in that: The shell is also provided with an external slag discharge port, which is connected to the bottom of the shell and is used to discharge the solid slag in the shell; the water outlet is higher than the external slag discharge port.

5. The aquaculture wastewater pretreatment filtering device according to claim 4, characterized in that: Slag discharge valves are installed on the slag discharge port inside the screen and the slag discharge port outside the screen.

6. The aquaculture wastewater pretreatment filtering device according to claim 4, characterized in that: It also includes a slag discharge main pipe, and the slag discharge port inside the screen and the slag discharge port outside the screen are both connected to the slag discharge main pipe.

7. The aquaculture wastewater pretreatment filtration device according to claim 1, characterized in that: The stirring system includes a rotating shaft, a scraper support and a screen scraper; the rotating shaft is located at the center of the screen container, and the scraper support is respectively connected to the rotating shaft and the screen scraper to drive the screen scraper to rotate through the rotating shaft; the screen scraper is used to scrape off the solid slag attached to the screen container.

8. The aquaculture wastewater pretreatment filtering device according to claim 7, characterized in that: The stirring system further comprises a slag conveying screw connected to the rotating shaft and used for pushing down the solid slag when the rotating shaft rotates.

9. The aquaculture wastewater pretreatment filtering device according to claim 1, characterized in that: It also includes a pressure gauge and an exhaust port, which are installed on the top of the shell.

10. A method for pre-treatment and filtration of aquaculture wastewater, characterized in that: Using the aquaculture wastewater pretreatment filtration device as described in any one of claims 1 to 9 comprises the following steps: Step 1: The aquaculture wastewater to be treated is sent into the screen container from the water inlet, and the solid residue is trapped in the screen container and discharged through the slag discharge port inside the screen; the filtered aquaculture wastewater enters the shell set outside the screen container, the solid residue is discharged through the slag discharge port outside the screen, and the aquaculture wastewater is discharged from the water outlet; Step 2: After the pressure in the shell rises to a preset upper limit, stop conveying the aquaculture wastewater to the screen container, start the stirring system, and rotate the screen scraper to clean the solid residue attached to the inner wall of the screen container; Step 3: Start the backwash system to backwash the screen container with high-pressure air to blow the solid slag embedded in the mesh away from the mesh.

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