A negative pressure self-priming backwashing device

Abstract

A negative pressure self-priming backwashing device comprises a filter body shell, a primary filter chamber, a secondary filter chamber, a backwashing device and a controller. The primary filter chamber and the secondary filter chamber are both arranged inside the filter body shell, and a perforated partition is arranged between the two. The backwashing device comprises a backwashing sewage suction device and a closed vacuum device. The closed vacuum device comprises a backwashing drive chamber, a backwashing sewage suction pipe, a sewage sealing box, a submersible pump and a sewage discharge pipe. The backwashing drive chamber is arranged inside the filter body shell and is separated from the secondary filter chamber by a partition. The backwashing drive chamber and the sewage sealing box are connected by a backwashing sewage suction pipe. The submersible pump is arranged inside the sewage sealing box, and the backwashing sewage suction device is arranged inside the filter body shell; the submersible pump, the water inlet pressure sensor and the water outlet pressure sensor are all connected to the controller. The present invention adopts a submersible pump to pump and discharge so that negative pressure is generated in the filter body, thereby realizing the backwashing function of the filter of the low-pressure drip irrigation system.

Description

Technical Field

[0001] The invention relates to a backwashing device, in particular to a negative pressure self-priming backwashing device. Background Art

[0002] With the development of agriculture, the drip irrigation mode in water-saving irrigation is widely used. In order to meet the normal operation of the drip irrigation system, the requirements for the quality of irrigation water are particularly strict. The filter has become an indispensable equipment in irrigation.

[0003] At present, the primary filtration of irrigation water in micro-irrigation systems is mainly completed by mesh filters. When the traditional mesh filter is working, the water containing dirt enters the filter from the water inlet through the filter screen, and the dirt is intercepted on the filter screen. The filtered water is then discharged from the water outlet. This filter has a simple structure and operation, but the dirt will adhere to the filter screen and needs to be cleaned frequently. There are also some backwashing filters, which are mainly flushed by reverse water flow. At present, the working pressure of the automatic backwashing mesh filter is 30 meters (0.3MPa), and the backwashing pressure is required to be 20-25 meters (0.2-0.25MPa). The filter screen is cleaned by using the atmospheric pressure and the tail working pressure difference through the sewage solenoid valve. The pressure difference is generally above 10-15 meters (0.1-0.15MPa). The backwashing is not clean if the pressure difference is lower than 10 meters (0.1MPa). Therefore, in order to meet the automatic backwashing requirements of the drip irrigation system, the head working pressure is 25-30 meters (0.25-0.3MPa). At present, disposable drip irrigation belts are widely used. Due to low carbon and insufficient power supply from the power grid, the water outlet pressure of the drip irrigation head pump decreases under low voltage conditions of the regional power grid or a drop in groundwater levels. When the working pressure drops to 15-20 meters (0.15-0.2MPa), the automatic backwashing function has limited effect or even cannot be realized. Dirt clogging the filter affects the irrigation uniformity and use of the drip irrigation system. Summary of the invention

[0004] In order to overcome the drawbacks of the prior art, the present invention provides a negative pressure self-priming backwashing device, which uses a submersible pump to generate negative pressure in the filter body to achieve the backwashing function of the filter of the low-pressure drip irrigation system.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] A negative pressure self-priming backwashing device, the device comprises a filter body shell, a primary filter chamber, a secondary filter chamber, a backwashing device and a controller, the filter body shell has two ends blocked, the primary filter chamber and the secondary filter chamber are both arranged inside the filter body shell, a perforated partition is arranged between the two, a coarse filter is arranged in the primary filter chamber, a fine filter is arranged in the secondary filter chamber, the coarse filter and the fine filter have a certain gap with the inner wall of the filter body shell, the backwashing device comprises a backwashing sewage suction device and a closed vacuum device, the closed vacuum device comprises a backwashing drive chamber, a backwashing sewage suction pipe, a sewage sealing box, a submersible pump and a sewage discharge pipe, the backwashing The backwash drive chamber is arranged inside the filter body shell and is separated from the secondary filter chamber by a partition. The perforated partition and the partition are both sealed and connected to the inner wall of the filter body shell. The backwash drive chamber and the sewage sealing box are connected through the backwash sewage suction pipe. The submersible pump is arranged inside the sewage sealing box. The sewage pipe is connected to the sewage outlet of the submersible pump. The backwash sewage suction device is arranged inside the filter body shell; a water inlet and a water inlet pressure sensor are arranged on the outer wall of the primary filter chamber, a water outlet and a water outlet pressure sensor are arranged on the outer wall of the secondary filter chamber, and the submersible pump, the water inlet pressure sensor and the water outlet pressure sensor are all connected to the controller.

[0007] The above-mentioned negative pressure self-priming backwashing device, the backwashing sewage suction device includes a sewage suction rotating shaft, a sewage suction nozzle, a rotating injection pipe and a reciprocating screw, the sewage suction rotating shaft is set as a hollow tube with two ends blocked, one end passes through the center position of the perforated partition, and the other end passes through the center of the partition and the center of the side wall of one end of the filter body shell, and is connected to the reciprocating screw, the sewage suction rotating shaft is respectively connected to the perforated partition, the partition and one end of the filter body shell by linear bearings, the sewage suction rotating shaft and the linear bearing are sealed by a sealing gasket, a driving fixed chamber is arranged outside the end of the backwashing driving chamber, and the reciprocating screw The rod is arranged in the driving fixed chamber, and a guide vane is fixed on the inner upper wall of the driving fixed chamber adjacent to one end of the filter main body shell, and one end of the guide vane slides along the threaded mouth of the reciprocating screw, and the rotating injection pipe is connected to the sewage suction rotating shaft located inside the backwashing driving chamber, and the rotating injection pipe is symmetrically and vertically connected to the sewage suction rotating shaft, and water spray nozzles with opposite outlet water directions are arranged at both ends of the rotating injection pipe, and the sewage suction nozzles are connected to the sewage suction rotating shaft located inside the secondary filter chamber in an axial and circumferential direction with uniform intervals, and one end of the sewage suction nozzle is close to the fine filter screen.

[0008] The above-mentioned negative pressure self-priming backwashing device, the water spray nozzle is set to an inverted trumpet shape, the two water spray nozzles are respectively connected to the two ends of the rotating injection pipe at 90 degrees, and the diameter of the connecting end of the water spray nozzle and the rotating injection pipe is larger than the diameter of the water outlet end.

[0009] In the above-mentioned negative pressure self-priming backwashing device, the sewage suction nozzle is arranged in an arc shape near one end of the fine filter screen, which is consistent with the arc shape of the fine filter screen.

[0010] The above-mentioned negative pressure self-priming backwashing device, the sewage sealing box is a fully enclosed structure, and the top is a detachable sealing cover plate.

[0011] In the negative pressure self-priming backwashing device, the reciprocating screw is cross-arranged with threads, and the two ends of the thread opening between the two cross-threads are respectively connected.

[0012] The negative pressure self-priming backwashing device is provided with a solenoid valve on the sewage pipe, and the solenoid valve is connected to the controller.

[0013] In the negative pressure self-priming backwashing device, the filter body shell is configured to be cylindrical.

[0014] The beneficial effects of the present invention are:

[0015] The backwashing device of the present invention uses a sewage sealing box and a submersible pump to evacuate the inside of the filter main body shell, so that a negative pressure state lower than the atmospheric pressure is formed inside the filter main body shell, the pressure difference of backwashing is increased, and automatic backwashing can be achieved under a low pressure of 10-20 meters (0.10-0.2MPa) working pressure. During backwashing, the water nozzles at both ends of the rotating injection pipe are set in reverse, with hydraulic power as the power. Under the action of the reverse water injection force, the suction rotating shaft is driven to rotate circumferentially. At the same time, under the action of the reciprocating screw and the guide vane, the suction rotating shaft moves axially left and right. The backwashing process runs stably and the flushing effect is uniform, achieving all-round suction of the fine filter screen, and the suction process does not require external force to drive, which is more energy-saving. The water nozzle is set to an inverted trumpet type, so that when water is sprayed from the water nozzle, the flow rate increases, the reaction force provided increases, and the rotation movement of the backwashing component is more stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the structure of the negative pressure self-priming backwashing device of the present invention;

[0017] Figure 2 It is a schematic diagram of the structure of a closed vacuum pumping device;

[0018] Figure 3 It is a schematic diagram of the structure of the rotating injection tube;

[0019] Figure 4 Schematic diagram of the reciprocating screw structure.

[0020] In the figure: 1. filter body shell; 2. primary filter chamber; 3. secondary filter chamber; 4. controller; 5. perforated partition; 6. coarse filter; 7. fine filter; 8. backwash drive chamber; 9. backwash sewage pipe; 10. sewage sealing box; 10-1. sealing cover; 11. submersible pump; 12. sewage pipe; 13. partition; 14. water inlet; 15. water inlet pressure sensor; 16. water outlet; 17. water outlet pressure sensor; 18. sewage suction rotating shaft; 19. sewage suction nozzle; 20. rotating injection pipe; 20-1. water nozzle; 21. reciprocating screw; 22. drive fixed chamber; 23. guide vane; 24. solenoid valve. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the accompanying drawings.

[0022] See also Figure 1 and Figure 4The present invention discloses a negative pressure self-priming backwashing device, comprising a filter body shell 1, a primary filter chamber 2, a secondary filter chamber 3, a backwashing device and a controller 4. The filter body shell 1 is configured as a cylindrical tube with both ends blocked. The primary filter chamber 2 and the secondary filter chamber 3 are both configured inside the filter body shell 1, and a perforated partition plate 5 is configured between the two. A coarse filter screen 6 is configured in the primary filter chamber 2, and a fine filter screen 7 is configured in the secondary filter chamber 3. Both the coarse filter screen and the fine filter screen have a certain gap with the inner wall of the filter body shell. The backwashing device comprises a backwashing suction device and a closed vacuum device. The backwashing suction device It is arranged inside the filter main body shell 1, including a suction shaft 18, a suction nozzle 19, a rotary injection pipe 20 and a reciprocating screw 21. The suction shaft 18 is set as a hollow tube with both ends blocked, one end passes through the center position of the perforated partition 5, and the other end passes through the center of the partition 13 and the center of the side wall of one end of the filter main body shell 1, and is connected to the reciprocating screw 21. The suction shaft 18 is respectively connected to the perforated partition 5, the partition 13 and one end of the filter main body shell 1 by linear bearings, and a sealing gasket is used to seal the suction shaft 18 and the linear bearing, so that the suction shaft can rotate circumferentially and slide axially, and the seal is tight. When the dirt suction rotating shaft is working, it can rotate circumferentially and move axially to realize all-round suction of dirt backwashed from the fine filter screen. A driving fixed chamber 22 is arranged outside the end of the backwashing driving chamber 8, and the reciprocating screw 21 is arranged in the driving fixed chamber 22. A guide vane 23 is fixed on the inner upper wall of the driving fixed chamber 22 adjacent to one end of the filter main body housing 1, and one end of the guide vane 23 slides along the threaded mouth of the reciprocating screw 21. The dirt suction rotating shaft 18 located inside the backwashing driving chamber 8 is connected to the rotating injection pipe 20, and the rotating injection pipe 20 is symmetrical and perpendicular to the dirt suction rotating shaft 18. The rotary injection pipe 20 is connected with water nozzles 20-1 at both ends with opposite outlet water directions. Under the action of the reverse water spraying force, the suction shaft rotates axially and drives the reciprocating screw to rotate circumferentially. Under the guidance of the guide vane, the reciprocating screw moves axially at the same time to realize the axial reciprocating movement of the suction shaft 18. The suction nozzles 19 are connected in the axial and circumferential directions and are evenly spaced on the suction shaft 18 located inside the secondary filter chamber 3. One end of the suction nozzle 19 is close to the fine filter screen 7 and is set to a shape consistent with the arc of the fine filter screen, which is beneficial for the suction nozzle to rotate close to the fine filter screen and absorb the dirt backwashed from the fine filter screen.

[0023] See also Figure 1 and Figure 2The enclosed vacuum pumping device includes a backwashing drive chamber 8, a backwashing sewage suction pipe 9, a sewage sealing box 10, a submersible pump 11 and a sewage discharge pipe 12. The backwashing drive chamber 8 is arranged inside the filter body shell 1 and is separated from the secondary filter chamber 3 by a partition 13. The perforated partition 5 and the partition 13 are both sealed and connected to the inner wall of the filter body shell 1, so that the primary filter chamber, the secondary filter chamber and the backwashing drive chamber are independent sealed chambers. The backwashing drive chamber 8 and the sewage sealing box 10 are connected through the backwashing sewage suction pipe 9. The submersible pump 11 1 is arranged inside the sewage sealing box 10, the sewage discharge pipe 12 is connected with the sewage discharge port of the submersible pump 11, the outer wall of the primary filter chamber 2 is provided with a water inlet 14 and a water inlet pressure sensor 15, the outer wall of the secondary filter chamber 3 is provided with a water outlet 16 and a water outlet pressure sensor 17, the submersible pump 11, the water inlet pressure sensor 15 and the water outlet pressure sensor 17 are all connected with the controller 4, the sewage discharge pipe 12 is provided with a solenoid valve 24, the sewage sealing box 10) is a fully enclosed structure, and the top is a detachable sealing cover plate 10-1, which is convenient for the installation of the submersible pump.

[0024] See also Figure 3 The water spray nozzle 20-1 is set to an inverted trumpet shape, and the two water spray nozzles 20-1 are respectively connected to the two ends of the rotating spray pipe 20 at 90 degrees. The diameter of the connection end of the water spray nozzle 20-1 and the rotating spray pipe 20 is larger than the diameter of the water outlet end.

[0025] Working process: irrigation water enters the filter body shell from the water inlet, is filtered through the coarse filter and enters the primary filter chamber, and then enters the secondary filter chamber through the water hole on the perforated partition. After being filtered through the fine filter, the clean water flows out from the water outlet for agricultural irrigation. When the pressure difference between the water inlet pressure sensor 15 and the water outlet pressure sensor 17 reaches the set value, it means that a lot of dirt has accumulated on the inside of the fine filter. At this time, a backwashing process is performed. The controller 4 controls the submersible pump 11 and the solenoid valve 24 to open in linkage. The submersible pump pumps out the sewage in the sewage sealing box 10, so that the pressure in the suction rotating shaft 18 is lower than the external atmospheric pressure, generating negative pressure. The suction force is generated on the inside of the fine filter through the suction nozzle 19, so that the clean water outside the fine filter flows in the opposite direction, backwashing the dirt attached to the inside of the fine filter. The flushed dirt is then discharged through the suction nozzle 1 9 enters the dirt suction rotating shaft 18, and then is sprayed out by the two water spray nozzles 20-1 on the rotating spray pipe 20. The reverse force generated by the sprayed water drives the dirt suction rotating shaft 18, the dirt suction nozzle 19 and the reciprocating screw 21 to rotate circumferentially. The dirt suction nozzle 19 rotates circumferentially to achieve the circumferential washing and absorption of the dirt inside the fine filter 7. At the same time, the reciprocating screw 21 rotates circumferentially, and one end of the guide vane 23 is fixed, and the other end slides along the thread mouth, so that the reciprocating screw 21 moves back and forth along the axial direction, realizing the axial backwashing and absorption process of the fine filter 7. The dirt backwashed is discharged from the sewage outlet. During the backwashing process, the circumferential and reciprocating axial movement of the dirt suction nozzle 19 covers the entire inner side of the fine filter 7, so that the backwashing effect is optimized. When the backwashing time reaches the time set by the controller 4, the controller 4 turns off the submersible pump 11 and the solenoid valve 24, and the device resumes the normal filtering operation state. The controller continuously monitors the pressure difference between the inlet and outlet water pressures. During the backwashing process, the flushing water flow is small and does not affect the filtering process of the device, thereby achieving uninterrupted water supply to the device.

Claims

1. A negative pressure self-priming backwashing device, characterized in that: The device comprises a filter main body shell (1), a primary filter chamber (2), a secondary filter chamber (3), a backwashing device and a controller (4). The filter main body shell (1) is sealed at both ends. The primary filter chamber (2) and the secondary filter chamber (3) are both arranged inside the filter main body shell (1). A perforated partition plate (5) is arranged between the two. A coarse filter screen (6) is arranged in the primary filter chamber (2), and a fine filter screen (7) is arranged in the secondary filter chamber (3). Both the coarse filter screen and the fine filter screen have a certain gap with the inner wall of the filter main body shell. The backwashing device comprises a backwashing sewage suction device and a closed vacuum device. The closed vacuum device comprises a backwashing drive chamber (8), a backwashing sewage suction pipe (9), a sewage sealing box (10), a submersible pump (11) and a sewage discharge pipe (12). The backwashing drive chamber (8) is arranged in the filter main body shell (1). The interior of the filter housing (1) is separated from the secondary filter chamber (3) by a partition (13); the perforated partition (5) and the partition (13) are both sealed and connected to the inner wall of the filter body housing (1); the backwashing drive chamber (8) and the sewage sealing box (10) are connected via the backwashing sewage suction pipe (9); the submersible pump (11) is arranged inside the sewage sealing box (10); the sewage discharge pipe (12) is connected to the sewage discharge port of the submersible pump (11); and the backwashing sewage suction device is arranged inside the filter body housing (1); a water inlet (14) and a water inlet pressure sensor (15) are arranged on the outer wall of the primary filter chamber (2); a water outlet (16) and a water outlet pressure sensor (17) are arranged on the outer wall of the secondary filter chamber (3); and the submersible pump (11), the water inlet pressure sensor (15) and the water outlet pressure sensor (17) are all connected to the controller (4); The backwashing sewage suction device comprises a sewage suction rotating shaft (18), a sewage suction nozzle (19), a rotary injection pipe (20) and a reciprocating screw (21). The sewage suction rotating shaft (18) is configured as a hollow tube with two ends blocked, one end of which passes through the center of the perforated partition plate (5), and the other end of which passes through the center of the partition plate (13) and the center of the side wall of one end of the filter body shell (1) and is connected to the reciprocating screw (21). The sewage suction rotating shaft (18) is respectively connected to the perforated partition plate (5), the partition plate (13) and one end of the filter body shell (1) by linear bearings. A sealing gasket is used to seal the sewage suction rotating shaft (18) and the linear bearing. A drive fixing chamber (22) is provided on the outer side of the end of the backwashing drive chamber (8). The reciprocating screw (21) is arranged in the drive fixing chamber (22). A guide vane (23) is fixed on the inner upper wall of the movable fixed chamber (22) adjacent to one end of the filter main body housing (1), one end of the guide vane (23) slides along the threaded opening of the reciprocating screw (21), the rotary jet pipe (20) is connected to the dirt suction rotating shaft (18) located inside the backwashing drive chamber (8), the rotary jet pipe (20) is symmetrically and vertically connected to the dirt suction rotating shaft (18), both ends of the rotary jet pipe (20) are provided with water spray nozzles (20-1) with opposite outlet water directions, the dirt suction nozzles (19) are connected to the dirt suction rotating shaft (18) located inside the secondary filter chamber (3) at even intervals in the axial and circumferential directions, one end of the dirt suction nozzle (19) is close to the fine filter screen (7); the sewage discharge pipe (12) is provided with a solenoid valve (24).

2. The negative pressure self-priming backwashing device according to claim 1 is characterized in that: The water spray nozzle (20-1) is configured as an inverted trumpet shape, and the two water spray nozzles (20-1) are respectively connected to the two ends of the rotating spray pipe (20) at 90 degrees, and the diameter of the connection end between the water spray nozzle (20-1) and the rotating spray pipe (20) is larger than the diameter of the water outlet end.

3. The negative pressure self-priming backwashing device according to claim 2 is characterized in that: The end of the sewage suction nozzle (19) close to the fine filter (7) is arranged in an arc shape, which is consistent with the arc shape of the fine filter (7).

4. The negative pressure self-priming backwashing device according to claim 3 is characterized in that: The sewage sealing box (10) is a fully enclosed structure, with a detachable sealing cover plate (10-1) on the top.

5. The negative pressure self-priming backwashing device according to claim 4 is characterized in that: The reciprocating screw (21) is cross-arranged with threads, and the two ends of the thread opening between the two cross-threads are respectively connected.

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