Filter cloth for filter press

Abstract

The present invention provides a filter cloth for a filter press that can prevent dehydrated cake from adhering to the liquid supply plate by fastening the liquid supply plate to a liquid supply plate holder whose upper and lower ends are joined to the filter cloth, thereby eliminating any gap between the liquid supply plate and the filter cloth. [Solution] A filter cloth for a filter press has a liquid supply plate 8 sandwiched between a pair of filter cloths 1A, 1B suspended between filter plates 10, 10, and supplies raw liquid to a filtration chamber 14 formed between the filter cloths 1A, 1B for dehydration. The filter cloth is equipped with a liquid supply plate holder 15 having an upper hole 16 corresponding to the through hole 6 of the filter cloth 1 and a lower hole 17 corresponding to the liquid supply hole 23 of the liquid supply plate 8, and the upper and lower ends of the liquid supply plate holder 15 are joined to the filter cloth 1 to form a side opening 29 into which the liquid supply plate 8 can be inserted between the filter cloth 1 and the liquid supply plate 8, so that the dehydrated cake produced does not stick to the liquid supply plate 8.

Description

[Technical Field]

[0001] The present invention relates to a filter cloth for a filter press that prevents dehydrated cake from adhering to a liquid supply plate sandwiched between a pair of filter cloths suspended between filter plates. [Background technology]

[0002] A filter press has a pair of filter cloths suspended between parallel filter plates that can be opened and closed freely, and the raw liquid is supplied from a liquid supply plate attached to the filter cloths to a filtration chamber formed between the pair of filter cloths, where solid-liquid separation is performed by the filter cloths.

[0003] Patent Document 1 discloses a filter press in which a pair of filter cloths are suspended between an ordinary filter plate and a press filter plate, and a press plate (liquid supply plate) is attached to each of the filter cloths using bolts.

[0004] Patent document 2 discloses a filter press in which a pair of filter cloths is suspended between adjacent filter plates, a liquid delivery tool holder is fixed to one of the pair of filter cloths, and a liquid delivery tool (liquid supply plate) is inserted from above the liquid delivery tool holder so that both sides are engaged with joints within the liquid delivery tool holder. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Publication number 7-5847 [Patent Document 2] Patent No. 7037376 Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Document 1, a pressure plate is attached to each of a pair of filter cloths with bolts, leaving a gap between the filter cloths and the pressure plate. Therefore, if the raw liquid supplied to the filter chamber enters the gap and forms a cake, the resulting dehydrated cake adheres to the pressure plate. Furthermore, when the filter cloth is lowered and inverted to discharge the dehydrated cake, the dehydrated cake separates from the filter cloth, but a portion of the cake remains hanging down from the pressure plate, requiring manual removal.

[0007] In Patent Document 2, the liquid delivery tool is inserted from above into a liquid delivery holder attached to one of the filter cloths and both sides are engaged with the liquid delivery holder, so that the top and bottom of the liquid delivery holder are open and a gap is generated between the liquid delivery tool and the filter cloth. Therefore, if the raw liquid supplied to the filtration chamber gets into the gap and forms a cake, the resulting dehydrated cake sticks to the liquid delivery tool and hangs down.

[0008] The present invention provides a filter cloth for a filter press that can prevent dehydrated cake from adhering to the liquid supply plate by inserting the liquid supply plate into a liquid supply plate holder whose upper and lower ends are joined to the filter cloth, and holding the liquid supply plate in close contact with the filter cloth without any gaps. [Means for solving the problem]

[0009] The present invention relates to a filter cloth for a filter press in which a liquid supply plate is sandwiched between a pair of filter cloths suspended between filter plates, and raw liquid is supplied to a filtration chamber formed between the filter cloths for dehydration.The filter cloth is equipped with a liquid supply plate holder having upper holes corresponding to the through holes of the filter cloths and lower holes corresponding to the liquid supply holes of the liquid supply plate, and the upper and lower ends of the liquid supply plate holder are joined to the filter cloths to form side openings into which a liquid supply plate can be inserted between the filter cloths, so that the dehydrated cake produced does not stick to the liquid supply plate.

[0010] The liquid supply plate holder has its upper end sewn to one filter cloth and its lower end sewn to the other filter cloth to form an upper end joint and a lower end joint, respectively, and a fastener is fitted into the groove around the through hole of the liquid supply plate via the liquid supply plate holder to secure the liquid supply plate; alternatively, its upper and lower ends are sewn to the other filter cloth to form an upper end joint and a lower end joint, respectively, and a fastener is fitted into the groove around the through hole of the liquid supply plate via the liquid supply plate holder to secure the liquid supply plate, thereby allowing the liquid supply plate to be held tightly within the liquid supply plate holder and preventing the head of the fastener from coming into contact with the filter cloth and damaging the filter cloth. [Effects of the Invention]

[0011] In this invention, the feed plate is inserted through a side opening of the feed plate holder, the upper and lower ends of which are sewn to the filter cloth, and the feed plate is held in close contact with the filter cloth, eliminating any gaps between the feed plate and the filter cloth. This prevents dehydrated cake from forming in the gap, preventing it from adhering to the feed plate. Manual removal of dehydrated cake is also unnecessary, enabling stable unmanned operation. The weight of dehydrated cake hanging from the feed plate does not place a load on the filter cloth, improving the durability of the filter cloth. Furthermore, filtration efficiency is not reduced because the hanging cake does not clog the upper and lower holes. Furthermore, the formation of a pair of side openings allows the feed plate to be easily attached and detached from both sides of the feed plate holder, making it possible to replace the feed plate while the filter cloth is attached to the filter press body. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view of a pair of filter cloths to which liquid supply plates of a filter press according to the present invention are attached. [Figure 2] FIG. 2 is a side view of the main part of the filter press. [Figure 3] 1B is a plan view and a side view of the liquid supply plate. [Figure 4] This is an oblique view of the liquid supply plate holder attached to the filter cloth. [Figure 5] FIG. 10 is a schematic side view of the liquid supply plate holder attached to the filter cloth. [Figure 6] FIG. 10 is a schematic side view of a liquid supply plate holder attached to a filter cloth according to another embodiment of the present invention. [Figure 7] FIG. 10 is a perspective view of a liquid supply plate holder attached to a filter cloth according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] FIG. 1 is a perspective view of a pair of filter cloths to which liquid feed plates of a filter press according to the present invention are attached. The upper ends of a pair of filter cloths 1, 1 are joined together to form a bag portion 2, and a bag portion 3 is also formed at the lower end of the filter cloth 1. An upper filter cloth core metal 4 and a lower filter cloth core metal 5 are inserted into the upper bag portion 2 and the lower bag portion 3, respectively. A through hole 6 opened at the center of the top of the filter cloth 1 is aligned with a raw liquid passage 7 of a liquid supply plate 8, and the liquid supply plate 8 is sandwiched between the pair of filter cloths 1, 1. A liquid supply passage 9 branching off from the raw liquid passage 7 is formed in the liquid supply plate 8, so that raw liquid can be supplied between the pair of filter cloths 1, 1 from the liquid supply passage 9.

[0014] FIG. 2 is a side view of the main part of the filter press. A pair of filter cloths 1, 1 shown in Figure 1 are arranged between parallel filter plates 10, 10 so as to be able to open and close freely, and a drive chain 11 connected to both ends of the upper filter cloth core metal 4 of the filter cloth 1 is looped around a sprocket 12 supported on the shoulder of the filter plate 10.

[0015] The lower ends of the filter cloths 1 suspended at the front and rear of the filter plate 10 are respectively looped around return rolls 13 suspended at positions offset from the bottom of the filter plate 10, and both ends of a lower filter cloth core 5 inserted through the lower end of the filter cloth 1 are connected to the other ends of front and rear drive chains 11, respectively, allowing the filter cloth 1 to be raised and lowered in a seesaw manner. When the parallel filter plates 10 are closed, the liquid feed plate 8 provided between the filter cloths 1 is sandwiched between the front and rear filter plates 10, forming a filtration chamber 14 between the pair of filter cloths 1 stretched across the filtration bed of the filter plate 10. The liquid feed passage 7 of the liquid feed plate 8 is connected to the liquid feed passage formed in the filter plate 10, and the liquid is supplied from the liquid feed passage 9 of the liquid feed plate 8 to the filtration chamber 14, and solid-liquid separation is performed by the filter cloth 1.

[0016] FIG. 3 is a plan view and a side view of the liquid supply plate. A stock solution passage 7 penetrates the front and rear surfaces slightly above the center of the stock solution plate 8, and a stock solution passage 9 branches off downward from the stock solution passage 7. The stock solution passage 9 runs vertically through the center of the stock solution plate 8 to the bottom. A stock solution hole 23 is formed at the bottom, and stock solution that flows in from the stock solution passage 9 flows out downward.

[0017] The lower part of the liquid feed plate 8 is formed with a tapered section 24 so that accessory parts such as the filter cloth 1 that come into contact with the liquid feed plate 8 will not be damaged when the filter plate is closed. The liquid feed plate 8 is formed with a tapered section 24 not only at the bottom but all around, and the sections from the top end to the bottom on both sides are also tapered, so that the liquid feed plate 8 does not interfere with closing the filter plate 10 when it is closed in the position shown in Figure 2 during the filtration process.

[0018] A plurality of through holes 26 with inclined grooves 25, 25 formed on both sides are formed around the periphery of the concentrate passage 7 of the liquid supply plate 8. Each through hole 26 is a hole through which a fastener 27 is inserted, and when the fastener 27 is inserted, the head of the fastener 27 fits into the groove 25 so that the head of the fastener 27 does not protrude outward.

[0019] The front surface of the liquid feed plate 8 is fixed to the liquid feed plate holder 15, and the back surface is fixed to the filter cloth 1. Specifically, fasteners 27 are inserted from the front surface of the liquid feed plate 8 via the liquid feed plate holder 15, and are engaged with fasteners 28 that are installed from the back surface via the filter cloth 1. Since fasteners 28 also fit into the recessed grooves 25, fasteners 28 do not protrude outward. Note that openings 33 (FIG. 4) are formed in the liquid feed plate holder 15 and the filter cloth 1, through which fasteners 27 can be inserted.

[0020] By fitting the fasteners 27 and fastening members 28 into the recessed grooves 25, the fasteners 27 and fastening members 28 do not protrude outward, and therefore there is no risk of damaging the filter cloth 1, filter plate 10, or other accessories.

[0021] The structures and quantities of the fasteners 27 and the fastening members 28 are not limited, but for example, when a male screw threaded on the outside is used as the fastener 27, a female screw threaded on the inside is used as the fastener member 28, and the fastener 27 is screwed into the fastener member 28. A cylindrically formed female screw may be extended inside the through-hole 26, and two male screws 27, 27 may be inserted from both sides of the liquid supply plate 8 to screw them together.

[0022] Furthermore, when fastener 27 is a member having a plurality of flexible elastic legs (elastically deformable portions) 30 hanging down from head flange 18 formed in the shape of a countersunk screw and having locking claw 31 at the bottom, fastener member 28 is an annular member having groove-shaped locking portion 32 therein, and locking claw 31 is locked to locking portion 32. When multiple elastic legs 30 are inserted into through-hole 26 in a compressed state, the restoring force of each elastic leg 30 acts to lock locking claw 31 to lock locking portion 32.

[0023] In this embodiment, a groove 25 is provided in the liquid supply plate 8, but it is possible to implement appropriate modifications, such as not providing a groove 25 in the liquid supply plate 8, arranging the fasteners 27 and fastening members 28 so that they protrude outward from the liquid supply plate 8, and providing a recess (not shown) on the filter plate side to prevent damage to the accessories.

[0024] FIG. 4 is a perspective view of the liquid supply plate holder attached to the filter cloth. The liquid feed plate holder 15 is a single piece of filter cloth made of synthetic fibers such as PP, and is joined to the filter cloth 1 by sewing together its upper and lower ends. The liquid feed plate holder 15 is long enough to cover the liquid feed plate 8 from its upper end to its lower end, and by sewing together its upper and lower ends, a pair of side openings 29, 29 are formed between the filter cloth 1 and the liquid feed plate holder 15. In this embodiment, the entire upper and lower ends of the liquid feed plate holder 15 are sewn to the filter cloth 1, and the liquid feed plate 8 can be attached and detached through the formed side openings 29. The liquid feed plate 8 can be held by inserting it through the side openings 29 and placing it in the space formed between the upper end joint 19, the lower end joint 20, and the filter cloth 1.

[0025] The liquid supply plate holder 15 also has upper holes 16 formed at positions corresponding to the through holes 6 of the filter cloth 1, and lower holes 17 formed at positions corresponding to the liquid supply holes 23 of the liquid supply plate 8. While the above-mentioned side opening portions 29 are openings that open along the filtration surface of the filter cloth 1, the upper holes 16 and lower holes 17 are openings that open in a direction approximately perpendicular to the filtration surface of the filter cloth 1.

[0026] By inserting the liquid supply plate 8 from the side opening 29 and fixing it in place, the raw liquid supplied through the through holes 6 of the filter cloth 1 flows from the upper hole 16 of the liquid supply plate holder 15 through the liquid supply path 9 inside the liquid supply plate 8, and then through the liquid supply hole 23 and the lower hole 17 into the filtration chamber 14 formed between the pair of filter cloths 1, 1.

[0027] Note that the entire surface or a predetermined portion of one of the pair of side openings 29, 29 may be sewn to the filter cloth 1, so that the liquid feed plate 8 can be attached and detached from only one side. The widths of the liquid feed plate holder 15 in the vertical and horizontal directions are set so that the surface of the liquid feed plate 8 is covered when the liquid feed plate 8 is inserted, but the length in the vertical and horizontal directions, the joining positions of the upper and lower ends with the filter cloth 1, etc. are determined according to design conditions. Appropriate modifications are possible, such as using a joining means other than sewing, or changing the shape and positions of the upper hole 16 and lower hole 17.

[0028] FIG. 5 is a schematic side view of the liquid supply plate holder attached to the filter cloth. In this embodiment, the upper end of the liquid supply plate holder 15 is sewn to one of the pair of filter cloths 1A, 1B, namely, filter cloth 1A, to form an upper end joint 19. In addition, the lower end is sewn to the other filter cloth 1B to form a lower end joint 20.

[0029] The upper end joint 19 is sewn to one of the filter cloths 1A so that the upper end of the liquid supply plate holder 15 is positioned above the top of the liquid supply plate 8, and the lower end joint 20 is sewn to the other filter cloth 1B so that the lower end of the liquid supply plate holder 15 is positioned below the bottom of the liquid supply plate 8.

[0030] The upper and lower ends of the liquid feed plate holder 15 are sewn to the filter cloths 1A and 1B to form an upper end joint 19 and a lower end joint 20, thereby forming a pair of side openings 29, 29 on both sides. In this embodiment, the liquid feed plate 8 is inserted through the side opening 29, and is placed in the space formed between the liquid feed plate holder 15 and the filter cloths 1A and 1B. By closing the filter plate 10 in this state, the liquid feed plate 8 is held in close contact with the filter cloth 1B with no gaps, so no gaps are formed between the liquid feed plate 8 and the filter cloth 1B.

[0031] Therefore, even if the raw liquid supplied during the filtration process gradually rises from the bottom of the filtration chamber 14, it can be prevented from flowing into the gap between the liquid supply plate 8 and the filter cloth 1B. As a result, the dehydrated cake produced in the gap does not come into direct contact with the front and back of the liquid supply plate 8, and does not hang down from the liquid supply plate 8 when the filter plate 10 is opened. In addition, because the liquid supply plate holder 15 is disposed between the liquid supply plate 8 attached to the other filter cloth 1B and one filter cloth 1A, there is no need to separately provide a pad to prevent the liquid supply plate 8 from contacting one filter cloth 1A.

[0032] FIG. 6 is a schematic side view of a liquid supply plate holder attached to a filter cloth according to another embodiment, and FIG. 7 is a perspective view of the liquid supply plate holder attached to a filter cloth according to another embodiment. In FIG. 6, the upper and lower ends of the liquid supply plate holder 15 are sewn to the other filter cloth 1B of the pair of filter cloths 1A, 1B to form an upper end joint 19 and a lower end joint 20, respectively.

[0033] The upper end joint 19 is sewn to the other filter cloth 1B so that the upper end of the liquid supply plate holder 15 is positioned above the top of the liquid supply plate 8, and the lower end joint 20 is sewn to the other filter cloth 1B so that the lower end of the liquid supply plate holder 15 is positioned below the bottom of the liquid supply plate 8.

[0034] The stitching positions of the upper and lower ends of the liquid supply plate holder 15 are set according to the design conditions, but as shown in the figure, the upper end may be extended to the vicinity of the filter cloth stitching portion 21, so that the upper end is sandwiched between a pair of filter cloths 1A and 1B.

[0035] Specifically, as shown in Fig. 7, when forming the bag portion 2 of the pair of filter cloths 1A, 1B, the upper end of the liquid supply plate holder 15 is sandwiched between the filter cloths 1A, 1B and sewn together with the pair of filter cloths 1A, 1B. In this configuration, the filter cloth seam 21 serves as the upper end joint 19, so there is no need to separately form the upper end joint 19. The other configuration is the same as in Fig. 5 and is therefore not described here.

[0036] In this embodiment, the liquid supply plate 8 is held by the other filter cloth 1B of the pair of filter cloths 1A and 1B, but it may be attached to both of the pair of filter cloths 1A and 1B.

[0037] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. [Industrial Applicability]

[0038] The filter cloth for a filter press according to the present invention is equipped with a feed plate holder that tightly holds the feed plate against one of a pair of filter cloths, eliminating any gaps between the feed plate and the filter cloth. This prevents dehydrated cake from adhering to the feed plate and preventing it from sagging. The filter cloth can be used with a variety of raw liquids, including water supply sludge, sewage sludge, and industrial wastewater sludge, and is particularly effective with raw liquids containing organic matter that tends to adhere to resin or metal feed plates. [Explanation of symbols]

[0039] 1, 1A, 1B filter cloth 6 through hole 8 Liquid supply plate 10 filter plate 14 Filtration chamber 15 Liquid supply plate holder 16 Upper hole 17 Pre-drilling 19 Upper end joint 20 Lower end joint 23 Liquid supply hole 25 Groove 26 Through hole 27 Fasteners 29 Side opening

Claims

1. A filter cloth for a filter press in which a liquid supply plate (8) is sandwiched between a pair of filter cloths (1A, 1B) suspended between filter plates (10, 10), and raw liquid is supplied to a filtration chamber (14) formed between the filter cloths (1A, 1B) for dewatering, a liquid supply plate holder (15) having upper holes (16) corresponding to the through holes (6) of the filter cloth (1) and lower holes (17) corresponding to the liquid supply holes (23) of the liquid supply plate (8); The upper and lower ends of the liquid supply plate holder (15) are joined to the filter cloth (1) to form a side opening (29) between the filter cloth (1) and the liquid supply plate (8) into which the liquid supply plate (8) can be inserted. A filter cloth for a filter press characterized by:

2. The liquid supply plate holder (15) is The upper end is sewn to one filter cloth (1A) and the lower end is sewn to the other filter cloth (1B) to form an upper end joint (19) and a lower end joint (20), respectively; The fastener (27) is fitted into the groove (25) around the through-hole (26) of the liquid supply plate (8) via the liquid supply plate holder (15) to fasten the liquid supply plate (8).

2. The filter cloth for a filter press according to claim 1.

3. The liquid supply plate holder (15) is The upper and lower ends are sewn to the other filter cloth (1B) to form an upper end joint (19) and a lower end joint (20), respectively; The fastener (27) is fitted into the groove (25) around the through-hole (26) of the liquid supply plate (8) via the liquid supply plate holder (15) to fasten the liquid supply plate (8).

2. The filter cloth for a filter press according to claim 1.

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