Rotary drum filtering system

Abstract

The invention discloses a rotary drum filtering system which comprises a rotary drum, filter cloth coated on the peripheral wall of the rotary drum and a discharging scraper attached to the surface of the filter cloth, and further comprises a flushing structure with at least one water outlet, a water outlet of the flushing structure is formed below the unloading scraper and faces the surface of the filter cloth; the filter cloth after the filter cake is scraped off by the unloading scraper is flushed by the flushing structure, so that the continuity and the stability of the production process can be ensured on the basis of improving the cleanliness of fiber pores of the filter cloth, the filter cloth cleaning time can be saved, and the filter cloth regeneration efficiency can be improved.

Description

Technical Field

[0001] The invention belongs to the technical field of filtering equipment, and in particular relates to a rotary drum filtering system. Background Art

[0002] In the production of aqueous suspension polymerization process, the vacuum drum filtration system used for slurry filtration is the core equipment of the process production. The main function of the vacuum drum filtration system is gas-solid separation. The polymer generated by the polymerization reaction is filtered and separated from the suspended slurry mixture, and then sent to the drying system for drying through a screw feeder. The dehydration effect of the filter not only affects the steam consumption of the next drying process, but also affects the quality of the polymer. The regeneration effect of the filter cloth directly affects the permeability of the filter cloth, determines the thickness of the filter cake feeding and the dehydration effect of the filter. At the same time, due to the characteristics of the carbon fiber precursor polymerization process, the molecular weight distribution is wide, and low molecular polymers often block the vacuum drum filtration system filter cloth during the filtration process, affecting the service life of the filter cloth and causing the production process to be interrupted.

[0003] In the prior art, the process of improving the regeneration of the filter cloth in the vacuum drum filtration system involves back-blowing the filter cloth with compressed air or manually cleaning the filter cloth with a brush after it is completely disassembled to improve the unloading effect of the filter cloth and the cleanliness of the fiber pores of the filter cloth. However, due to the increase in the flow rate and pressure of the back-blowing compressed air, the winding wire that fixes the filter cloth often loosens and moves out of place, and the process of re-winding the fixing wire is seriously affected. In addition, manually cleaning the completely disassembled filter cloth with a brush consumes a lot of time and affects continuous production.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies in the prior art and provide a rotary drum filtration system, which utilizes a flushing structure to flush the filter cloth after the filter cake is scraped off by a discharging scraper, thereby improving the cleanliness of the filter cloth fiber pores, thereby achieving the purpose of ensuring the continuity and stability of the production process, saving the time for cleaning the filter cloth, and improving the efficiency of filter cloth regeneration.

[0006] In order to solve the above technical problems, the basic concept of the technical solution adopted by the present invention is:

[0007] The present invention provides a rotary drum filtering system, comprising a rotary drum, a filter cloth coated on the outer peripheral wall of the rotary drum, and a discharge scraper attached to the surface of the filter cloth.

[0008] Also included is a flushing structure having at least one water outlet;

[0009] The water outlet of the flushing structure is arranged below the discharge scraper and faces the surface of the filter cloth.

[0010] Further, the flushing structure is a spray-type flushing structure;

[0011] When the spray-type flushing structure has at least two spray ports, the at least two spray ports are arranged along the axial direction of the drum.

[0012] Further, the spray-type flushing structure comprises at least one spray nozzle and a flushing water delivery unit, and the spray nozzle has a spray port;

[0013] At least one spray nozzle is arranged at the water outlet end of the flushing water delivery unit and is spaced apart from the filter cloth;

[0014] When the spray-type flushing structure includes at least two spray nozzles, the at least two spray nozzles are arranged in an axial direction of the drum.

[0015] Further, the flushing water delivery unit includes a main waterway, an auxiliary waterway, and a booster pump connected in series to the auxiliary waterway;

[0016] The main water channel is arranged below the discharge scraper and extends from one end of the drum to the other end along the axial direction of the drum;

[0017] The main water channel has a water inlet and at least one water outlet connected to the auxiliary water channel, and each water outlet is provided with a spray nozzle;

[0018] When the spray-type flushing structure includes at least two spray nozzles, the main water channel has at least two water outlets arranged along the axial direction of the drum.

[0019] Furthermore, it also includes a fixed groove plate for supporting and installing a discharge scraper;

[0020] The fixed slot plate extends vertically and is spaced apart from the filter cloth;

[0021] The main water channel is arranged in the space between the fixed slot plate and the filter cloth, and the auxiliary water channel penetrates into the space between the fixed slot plate and the filter cloth from downward to upward and is communicated with the spray nozzle.

[0022] Furthermore, a filter pulp tank for storing filter pulp to be filtered is provided below the drum;

[0023] The spray nozzle faces the opening on the top of the filter tank;

[0024] The auxiliary waterway first extends to the top of the filter slurry tank opening, and then extends upward to communicate with the water inlet of the main waterway;

[0025] The booster pump is connected in series to the auxiliary waterway which is not directly opposite to the filter slurry tank opening.

[0026] Further, the spray nozzle is a fan-shaped spray nozzle with a spray angle of 45-60 degrees;

[0027] The angle between the direction of the water flow sprayed by the spray nozzle toward the filter cloth surface and the horizontal plane is 3-15 degrees.

[0028] Furthermore, a water retaining structure is provided at the bottom of the fixed trough plate;

[0029] The water retaining structure is arranged opposite to the spraying area formed by all the spraying nozzles on the filter cloth.

[0030] Further, the water retaining structure is a vertically extending water retaining plate;

[0031] The water baffle is spaced apart from the filter cloth and extends from one end of the drum to the other end along the axial direction of the drum;

[0032] The water retaining plate is open to the filter slurry tank, the top of which is connected to the bottom of the fixed tank plate, and the bottom of which extends downward to the bottom of the spraying area formed by all the spray nozzles on the filter cloth;

[0033] The auxiliary waterway passes through the space between the water retaining plate and the filter cloth from bottom to top, and enters the space between the fixed slot plate and the filter cloth to communicate with the main waterway.

[0034] Further, it also includes a compressed air pipeline for back-blowing the filter cloth to loosen the filter cake;

[0035] A back-blowing valve and a pressure detection device are connected in series on the compressed air pipeline;

[0036] The back-blowing valve and the pressure sensor are arranged in sequence along the flow direction of the compressed air;

[0037] The degree of clogging of the filter cloth is judged according to the pressure value detected by the pressure detection device, and the pressure of the flushing water of the flushing structure is adjusted accordingly.

[0038] After adopting the above technical scheme, the present invention has the following beneficial effects compared with the prior art.

[0039] By utilizing the flushing structure to flush the filter cloth after the filter cake is scraped off by the discharge scraper, the cleanliness of the filter cloth fiber pores can be improved, the continuity and stability of the production process can be ensured, the time for cleaning the filter cloth can be saved, and the efficiency of filter cloth regeneration can be improved.

[0040] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings are part of the present invention and are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation of the present invention. Obviously, the accompanying drawings described below are only some embodiments. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0042] Figure 1 A schematic diagram of the structure of a rotary drum filter system provided by an embodiment of the present invention;

[0043] Figure 2 This is a working principle diagram of the rotary drum filtration system provided in an embodiment of the present invention.

[0044] Icons: 1-drum; 2-filter cloth; 3-discharging scraper; 4-flushing structure; 41-spray nozzle; 42-flushing water delivery unit; 421-main water channel; 422-auxiliary water channel; 423-boosting pump; 5-fixed trough plate; 6-filter slurry trough; 61-filter slurry trough opening; 7-water retaining structure; 71-water retaining plate; 8-compressed air pipeline; 9-backblowing valve; 10-pressure detection device; 101-pressure sensor; 11-filter cake forming area; 12-drying area; 13-first resting area; 14-backblowing area; 15-second resting area.

[0045] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0047] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0048] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] like Figure 1 As shown, the present invention provides a drum 1 filtering system, comprising a drum 1, a filter cloth 2 coated on the outer peripheral wall of the drum 1, and a discharge scraper 3 attached to the surface of the filter cloth 2.

[0050] Also includes a flushing structure 4 having at least one water outlet;

[0051] The water outlet of the flushing structure 4 is arranged below the discharge scraper 3 and faces the surface of the filter cloth 2 .

[0052] In the embodiment of the present invention, by utilizing the flushing structure 4 to flush the filter cloth 2 after the filter cake is scraped off by the discharge scraper 3, the cleanliness of the fiber pores of the filter cloth 2 can be improved, the continuity and stability of the production process can be ensured, the time for cleaning the filter cloth 2 can be saved, and the efficiency of regeneration of the filter cloth 2 can be improved.

[0053] The drum 1 is usually a rotating cylindrical structure. During the filtering process, the drum 1 will continuously rotate to assist the filter cloth 2 in the filtering operation.

[0054] The filter cloth 2 is coated on the outer wall of the drum 1, and its main function is to filter out solid particles in the liquid or gas; when the liquid or gas containing impurities passes through the filter cloth 2, the impurities will be intercepted by the filter cloth 2 and form a filter cake on the surface of the filter cloth 2; when the drum 1 filtering system filters the liquid, a filter slurry tank 6 for containing the liquid is provided under the drum 1;

[0055] The discharge scraper 3 is closely attached to the surface of the filter cloth 2. As the drum 1 rotates, the discharge scraper 3 scrapes off the filter cake trapped on the surface of the filter cloth 2, thereby maintaining the filtering efficiency of the filter cloth 2. The design of the discharge scraper 3 is usually to ensure that impurities can be effectively scraped off the filter cloth 2 and collected at a designated location.

[0056] The flushing structure 4 is used to flush the surface of the filter cloth 2 to ensure that it maintains good filtering performance for a long time. When the flushing structure 4 is working, water or other flushing liquid will flow out from the water outlet to flush the surface of the filter cloth 2, thereby flushing away fine impurities or blockages that may remain on the filter cloth 2, preventing the filter cloth 2 from being blocked and regenerating the filter cloth 2;

[0057] The unloading scraper 3 first scrapes off the filter cake on the filter cloth 2, and then the flushing structure 4 further cleans the filter cloth 2, thereby ensuring that the filter cloth 2 always maintains a good filtering effect.

[0058] In addition, it should be noted that the drum 1 filtration system of the present application includes a frame, and the drum 1, the flushing structure 4, the fixed slot plate 5 described below, etc. can be arranged on the bracket.

[0059] Figure 2The working principle diagram of the drum 1 filtering system is shown. When working, a filter cake forming area 11, a suction drying area 12, a first resting area 13, a back-blowing area 14 and a second resting area 15 are formed in sequence along the circumference of the drum 1. The filter cake is on the filter cloth 2 area of ​​the filter cake forming area 11, the suction drying area 12, the first resting area 13 and the back-blowing area 14; the flushing structure 4 flushes the filter cloth 2 area of ​​the second resting area 15, and the filter cake has been scraped off the filter cloth 2 area by the unloading scraper 3.

[0060] In the embodiment of the present invention, the flushing structure 4 is a spray-type flushing structure;

[0061] When the spray-type flushing structure has at least two spray ports, the at least two spray ports are arranged in an axial direction of the drum 1 .

[0062] In the embodiment of the present invention, the flushing structure 4 is a spray-type flushing structure, that is, the flushing structure 4 works in a spraying manner. The spray-type flushing structure usually sprays water or other flushing liquid at a certain pressure and flow rate through the spray nozzle 41 to form a fine water mist or water column to evenly flush the surface of the filter cloth 2. This flushing method can more effectively remove impurities and blockages on the filter cloth 2, while reducing the wear on the filter cloth 2.

[0063] When the spray-type flushing structure has at least two spray ports, these spray ports are arranged along the axial direction of the drum 1 to ensure that water or other flushing liquid can evenly cover the entire surface of the filter cloth 2; this arrangement can ensure that any part of the filter cloth 2 can be fully flushed during the rotation process, thereby improving the flushing effect.

[0064] The spray-type flushing structure of the present application may have one spray port or at least two spray ports;

[0065] The number and arrangement of the spray ports can be adjusted according to the specific filtering requirements and equipment size; for example, for larger drum 1 and filter cloth 2 areas, the number of spray ports can be increased to improve flushing efficiency; for areas that require special cleaning, the arrangement of the spray ports can be adjusted to ensure that the flushing liquid can be accurately sprayed into the area; for another example, the number of spray ports is fixed, and control valves can be provided at the spray ports. For larger drum 1 and filter cloth 2 areas, all spray ports can be fully opened by opening all control valves. For smaller drum 1 and filter cloth 2 areas, the number of spray ports opened can be reduced by opening and closing the number of control valves, so that the flushing structure 4 can adapt to various models of drums 1 and filter cloths 2.

[0066] In the embodiment of the present invention, the spray-type flushing structure includes at least one spray nozzle 41 and a flushing water delivery unit 42, and the spray nozzle 41 has a spray port;

[0067] At least one spray nozzle 41 is disposed at the water outlet of the flushing water delivery unit 42 and is spaced apart from the filter cloth 2;

[0068] When the spray-type flushing structure includes at least two spray nozzles 41 , the at least two spray nozzles 41 are arranged in an axial direction of the drum 1 .

[0069] In the embodiment of the present invention, the flushing structure 4 is mainly composed of at least one spray nozzle 41 and a flushing water delivery unit 42. The spray nozzle 41 is a key component for performing the flushing action, and the flushing water delivery unit 42 is responsible for providing the spray nozzle 41 with the required water or other flushing liquid.

[0070] The spray nozzle 41 has a spray port, which can be considered as an outlet for the flushing liquid to be sprayed out. By adjusting the shape, size and angle of the spray port, the spray range, flow rate and pressure of the flushing liquid can be controlled, thereby achieving effective flushing of the surface of the filter cloth 2. The flushing water delivery unit 42 is the power source of the spray flushing structure, and is responsible for delivering the flushing liquid to the spray nozzle 41.

[0071] When the spray-type flushing structure includes only one spray nozzle 41 , the spray nozzle 41 will be arranged at the water outlet end of the flushing water supply unit so as to spray water or other flushing liquid directly onto the surface of the filter cloth 2 .

[0072] When the spray-type flushing structure includes at least two spray nozzles 41, these spray nozzles 41 are arranged along the axial direction of the drum 1. This arrangement can ensure that the flushing liquid can evenly cover the entire surface of the filter cloth 2, thereby improving the flushing effect. At the same time, according to the length of the drum 1 and the area of ​​the filter cloth 2, the number and arrangement of the spray nozzles 41 can be adjusted to meet different flushing requirements.

[0073] Specifically, the flushing water delivery unit 42 includes a main waterway 421, an auxiliary waterway 422, and a booster pump 423 connected in series to the auxiliary waterway 422;

[0074] The main water channel 421 is arranged below the discharging scraper 3 and extends from one end of the drum 1 to the other end along the axial direction of the drum 1;

[0075] The main water channel 421 has a water inlet and at least one water outlet connected to the auxiliary water channel 422, and each water outlet is provided with a spray nozzle 41;

[0076] When the spray-type flushing structure includes at least two spray nozzles 41 , the main water channel 421 has at least two water outlets arranged along the axial direction of the drum 1 .

[0077] The flushing water delivery unit 42 may also include components such as a water tank and a filter for storing water or other flushing liquids. The water tank is connected to the water inlet of the auxiliary water channel 422, and the filter is arranged on the auxiliary water channel 422 to ensure that the cleanliness of the water or other flushing liquid delivered to the spray nozzle 41 meets the flushing requirements.

[0078] Such a layout of the main water channel 421 can ensure that the flushing water can evenly cover the entire axial length of the drum 1, thereby improving the flushing effect.

[0079] The main waterway 421 has a water inlet connected to the auxiliary waterway 422, which is the entrance for the flushing water to enter the main waterway 421. At the same time, the main waterway 421 also has at least one water outlet, each of which is provided with a spray nozzle 41. The number of water outlets and spray nozzles 41 can be adjusted according to the length of the drum 1 and the filter cloth 2 and the flushing requirements to ensure the uniformity and efficiency of the flushing. The arrangement of the water outlets on the main waterway 421 can ensure that the flushing water can be evenly sprayed to various positions on the surface of the filter cloth 2, thereby further improving the flushing effect.

[0080] The function of the booster pump 423 is to increase the pressure of the flushing water to ensure that the flushing water can smoothly pass through the main water channel 421 and the spray nozzle 41 and be sprayed to the surface to be flushed with sufficient pressure. The flushing water pressure is controlled at 0.8-1.5MPa and the flushing water temperature is controlled at 75-85℃.

[0081] In the embodiment of the present invention, it also includes a fixed groove plate 5 for supporting and installing the unloading scraper 3;

[0082] The fixed slot plate 5 extends vertically and is spaced apart from the filter cloth 2;

[0083] The main water channel 421 is arranged in the space between the fixed slot plate 5 and the filter cloth 2 , and the auxiliary water channel 422 penetrates from bottom to top into the space between the fixed slot plate 5 and the filter cloth 2 and communicates with the spray nozzle 41 .

[0084] In the embodiment of the present invention, the unloading scraper 3 is hingedly arranged with the fixed slot plate 5; the fixed slot plate 5 extends vertically and maintains a certain distance from the filter cloth 2. Such a design can ensure that the unloading scraper 3 can stably scrape away impurities on the surface of the filter cloth 2 when working, while avoiding excessive friction or damage with the filter cloth 2, and providing space for the installation of the subsequent spray nozzle 41;

[0085] The main water channel 421 is arranged in the space between the fixed slot plate 5 and the filter cloth 2. Such a layout can make full use of this space and avoid causing additional interference to the overall structure of the equipment. At the same time, since the main water channel 421 is located below the discharge scraper 3, it can ensure that the flushing water can be directly sprayed onto the surface of the filter cloth 2 where the filter cake is removed by the discharge scraper 3, effectively flushing away the residual impurities.

[0086] The auxiliary water channel 422 penetrates into the space between the fixed slot plate 5 and the filter cloth 2 from below and is connected to the spray nozzle 41. This means that after the flushing water is pressurized by the booster pump 423, it will rise along the auxiliary water channel 422 to the space between the fixed slot plate 5 and the filter cloth 2, and be sprayed onto the surface of the filter cloth 2 through the spray nozzle 41. This design ensures that the flushing water can be sprayed to the area that needs to be flushed with sufficient pressure and flow.

[0087] The layout design of the fixed trough plate 5, the main water channel 421 and the auxiliary water channel 422 not only improves the structural stability and reliability of the equipment, but also ensures the effectiveness and efficiency of the flushing system. This design enables the equipment to maintain a stable flushing effect during long-term operation, thereby extending the service life of the filter cloth 2 and improving the performance of the entire filtration system.

[0088] Furthermore, a filter pulp tank 6 for storing filter pulp to be filtered is provided below the drum 1;

[0089] The spray nozzle 41 is directly facing the opening on the top of the slurry filtering tank 6;

[0090] The auxiliary water channel 422 first extends to the top of the filter slurry tank opening 61, and then extends upward to communicate with the water inlet of the main water channel 421;

[0091] The booster pump 423 is connected in series to the auxiliary water channel 422 which is not directly opposite to the filter slurry tank opening 61 .

[0092] The filter pulp to be filtered refers to the original pulp that has not been filtered by the filter cloth 2. The filter pulp to be filtered enters the drum 1 for filtration;

[0093] The spray nozzle 41 is directly opposite to the opening on the top of the filter slurry tank 6, so that the flushing water sprayed from the spray nozzle 41 can enter the filter slurry tank 6 through the filter slurry tank opening 61 after flushing the filter cloth 2, thereby avoiding waste of water resources.

[0094] Specifically, the auxiliary water channel 422 can first extend horizontally to the top of the filter slurry tank opening 61, and then extend vertically upward to the water inlet of the main water channel 421; such a layout of the auxiliary water channel 422 can ensure the smoothness of the water flow and the stability of the pressure to reduce pressure loss and energy consumption; at the same time, it is easy to maintain and repair.

[0095] The booster pump 423 is connected in series to the auxiliary water channel 422 which is not directly opposite to the filter slurry tank opening 61, so as to facilitate the maintenance and overhaul of the pump.

[0096] Specifically, the spray nozzle 41 is a fan-shaped spray nozzle with a spray angle of 45-60 degrees;

[0097] The angle between the direction in which the spray nozzle 41 sprays water toward the surface of the filter cloth 2 and the horizontal plane is 3-15 degrees.

[0098] The spray port of the spray nozzle 41 faces downward and toward the filter cloth 2. The spray angle determines the coverage of the water flow sprayed by the spray nozzle 41 on the horizontal plane. The fan-shaped spray nozzle can evenly distribute the water flow in a wider range, thereby effectively cleaning the surface of the filter cloth 2.

[0099] The spray angle of 45-60 degrees is an optimized range, which can ensure sufficient water flow coverage while avoiding excessive dispersion of the water flow, resulting in poor cleaning effect.

[0100] The angle determines the contact angle between the water jetted from the spray nozzle 41 and the surface of the filter cloth 2; a proper angle can ensure that the water jet hits the surface of the filter cloth 2 at a proper angle, thereby more effectively cleaning the impurities attached to the filter cloth 2. The angle range of 3-15 degrees is carefully designed to ensure that the water jet has sufficient impact force to clean the filter cloth 2, while avoiding the situation where the angle is too large, causing the water jet to directly flush the edge of the filter cloth 2, causing unnecessary wear and weakening the flushing water pressure; and a too small angle causes the flushing water to splash.

[0101] By adjusting the distance between the spray nozzle 41 and the filter cloth 2 , the water mist effect of the two adjacent fan-shaped spray nozzles is realized to form an isosceles triangle, evenly covering the surface of the filter cloth 2 .

[0102] In the embodiment of the present invention, a water retaining structure 7 is provided at the bottom of the fixed groove plate 5;

[0103] The water retaining structure 7 is arranged opposite to the spraying area formed by all the spraying nozzles 41 on the filter cloth 2 .

[0104] In the embodiment of the present invention, the main function of the water retaining structure 7 is to prevent the water generated during the spraying process from directly dripping into the non-working area of ​​the filtration system, such as the ground, the inside of the equipment or other parts that do not need to be contacted by the water.

[0105] The water retaining structure 7 is arranged opposite to the spraying area formed by all the spraying nozzles 41 on the filter cloth 2, which means that the position and shape of the water retaining structure 7 are determined according to the layout of the spraying nozzles 41 and the size of the spraying area.

[0106] The water retaining structure 7 works together with the spray nozzle 41 to ensure that the water flow generated during the spraying process can evenly cover the surface of the filter cloth 2, while preventing the water flow from overflowing or dripping into the non-working area.

[0107] When designing the water retaining structure 7, factors such as the spray angle of the spray nozzle 41, the spray intensity, the shape and size of the spray area, etc. need to be considered to ensure that the water retaining structure 7 can effectively block the water flow without affecting the spraying effect.

[0108] Specifically, the water retaining structure 7 is a vertically extending water retaining plate 71;

[0109] The water baffle 71 is spaced apart from the filter cloth 2 and extends from one end of the drum 1 to the other end along the axial direction of the drum 1;

[0110] The water retaining plate 71 is directly opposite to the filter slurry tank opening 61, the top of which is connected to the bottom of the fixed tank plate 5, and the bottom of which extends downward to the bottom of the spraying area formed by all the spray nozzles 41 on the filter cloth 2;

[0111] The auxiliary water channel 422 passes from bottom to top through the space between the water retaining plate 71 and the filter cloth 2 into the space between the fixed slot plate 5 and the filter cloth 2 and communicates with the main water channel 421 .

[0112] The water retaining plate 71 is a structure extending in the vertical direction, and is usually in the shape of a flat plate;

[0113] The top of the water baffle 71 is closely connected to the bottom of the fixed groove plate 5 to form a continuous blocking surface. This design ensures that the water flow is effectively blocked between the water baffle 71 and the fixed groove plate 5 to prevent it from overflowing. The water baffle 71 extends downward to the bottom of the spray area to further enhance the blocking effect on the spray water.

[0114] The water baffle 71 faces the filter trough opening 61, and can guide the splashing flushing water into the filter trough 6; the auxiliary waterway 422 can make full use of the space between the water baffle 71, the fixed trough plate 5 and the filter cloth 2. The water baffle 71 is designed as a fiber soft type.

[0115] like Figure 2 As shown, in the embodiment of the present invention, it also includes a compressed air pipeline 8 for back-blowing the filter cloth 2 to loosen the filter cake;

[0116] A back-blowing valve 9 and a pressure detection device 10 are connected in series to the compressed air pipeline 8;

[0117] The blowback valve 9 and the pressure sensor 101 are arranged in sequence along the flow direction of the compressed air;

[0118] The degree of clogging of the filter cloth 2 is determined according to the pressure value detected by the pressure detection device 10, and the pressure of the flushing water of the flushing structure 4 is adjusted accordingly.

[0119] In an embodiment of the present invention, the compressed air pipeline 8 provides compressed air to the back-blowing area 14. During continuous filtration or long-term filtration, filter cakes are easily accumulated on the filter cloth 2, resulting in a decrease in filtration efficiency. By back-blowing compressed air, the filter cakes can be effectively loosened and the filtration efficiency can be improved. The back-blowing valve 9 is used to control the on-off of compressed air. When it is necessary to back-blow the filter cloth 2, the back-blowing valve 9 is opened, and when it is not necessary to back-blow, the back-blowing valve 9 is closed to prevent the compressed air from being lost unnecessarily; the back-blowing compressed air pressure is controlled at 0.05-0.2MPa.

[0120] The pressure sensor 101 is used to monitor the pressure value in the compressed air pipeline 8 in real time, and this pressure value can reflect the degree of blockage of the filter cloth 2. When the filter cloth 2 is seriously blocked, the resistance of the compressed air passing through the filter cloth 2 increases, and the pressure in the pipeline will also increase accordingly.

[0121] When the pressure value exceeds the set threshold, it means that the filter cloth 2 is seriously blocked. At this time, it is necessary to adjust the flushing water pressure of the flushing structure 4 to enhance the flushing effect and remove the blockage on the filter cloth 2. The flushing water pressure is determined by the booster pump; the flushing water pressure of the flushing structure 4 can be achieved by adjusting the speed of the booster pump 423, the opening of the valve, etc. When it is detected that the filter cloth 2 is blocked more, the flushing water pressure can be appropriately increased to improve the flushing effect; when the filter cloth 2 is blocked less, the flushing water pressure can be reduced accordingly to save energy.

[0122] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment, it is not used to limit the present invention. Any technician familiar with this patent can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. A rotary drum filtration system, comprising a rotary drum, a filter cloth wrapped on the outer peripheral wall of the rotary drum and a discharge scraper attached to the surface of the filter cloth, characterized in that: Also included is a flushing structure having at least one water outlet; The water outlet of the flushing structure is arranged below the discharge scraper and faces the surface of the filter cloth.

2. The rotary drum filter system according to claim 1, characterized in that: The flushing structure is a spray type flushing structure; When the spray-type flushing structure has at least two spray ports, the at least two spray ports are arranged along the axial direction of the drum.

3. The rotary drum filter system according to claim 2, characterized in that: The spray-type flushing structure comprises at least one spray nozzle and a flushing water delivery unit, wherein the spray nozzle has a spray port; At least one spray nozzle is arranged at the water outlet end of the flushing water delivery unit and is spaced apart from the filter cloth; When the spray-type flushing structure includes at least two spray nozzles, the at least two spray nozzles are arranged in an axial direction of the drum.

4. The rotary drum filter system according to claim 3, characterized in that: The flushing water delivery unit includes a main waterway, an auxiliary waterway and a booster pump connected in series to the auxiliary waterway; The main water channel is arranged below the discharge scraper and extends from one end of the drum to the other end along the axial direction of the drum; The main water channel has a water inlet and at least one water outlet connected to the auxiliary water channel, and each water outlet is provided with a spray nozzle; When the spray-type flushing structure includes at least two spray nozzles, the main water channel has at least two water outlets arranged along the axial direction of the drum.

5. The rotary drum filter system according to any one of claims 1 to 4, characterized in that: It also includes a fixed groove plate for supporting and installing a discharge scraper; The fixed slot plate extends vertically and is spaced apart from the filter cloth; The main water channel is arranged in the space between the fixed slot plate and the filter cloth, and the auxiliary water channel penetrates into the space between the fixed slot plate and the filter cloth from downward to upward and is communicated with the spray nozzle.

6. The rotary drum filter system according to claim 5, characterized in that: A filter slurry tank for storing filter slurry to be filtered is provided below the drum; The spray nozzle faces the opening on the top of the filter tank; The auxiliary waterway first extends to the top of the filter slurry tank opening, and then extends upward to communicate with the water inlet of the main waterway; The booster pump is connected in series to the auxiliary waterway which is not directly opposite to the filter slurry tank opening.

7. The rotary drum filter system according to claim 5, characterized in that: The spray nozzle is a fan-shaped spray nozzle with a spray angle of 45-60 degrees; The angle between the direction of the water flow sprayed by the spray nozzle toward the filter cloth surface and the horizontal plane is 3-15 degrees.

8. The rotary drum filter system according to any one of claims 1 to 7, characterized in that: A water retaining structure is provided at the bottom of the fixed trough plate; The water retaining structure is arranged opposite to the spraying area formed by all the spraying nozzles on the filter cloth.

9. The rotary drum filter system according to claim 8, characterized in that: The water retaining structure is a vertically extending water retaining plate; The water baffle is spaced apart from the filter cloth and extends from one end of the drum to the other end along the axial direction of the drum; The water retaining plate is open to the filter slurry tank, the top of which is connected to the bottom of the fixed tank plate, and the bottom of which extends downward to the bottom of the spraying area formed by all the spray nozzles on the filter cloth; The auxiliary waterway passes through the space between the water retaining plate and the filter cloth from bottom to top, and enters the space between the fixed slot plate and the filter cloth to communicate with the main waterway.

10. The rotary drum filter system according to any one of claims 1 to 9, characterized in that: It also includes a compressed air line for back-blowing the filter cloth to loosen the filter cake; A back-blowing valve and a pressure detection device are connected in series on the compressed air pipeline; The back-blowing valve and the pressure sensor are arranged in sequence along the flow direction of the compressed air; The degree of clogging of the filter cloth is judged according to the pressure value detected by the pressure detection device, and the pressure of the flushing water of the flushing structure is adjusted accordingly.

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