JPH0338881B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a filter plate for a single filter press, and more particularly to a filter plate for a single filter press that is capable of filtration and compression dehydration.

[Conventional technology]

Conventionally, the filter plate of a filter press that performs compression dehydration after filtration is of a type in which the filtration wall surface is moved inside the filtration chamber during the compression process, that is, an elastic membrane is placed on the core plate surface of the filter plate to perform compression filtration. form a board,
Those that supply and discharge pressure fluid between the membrane and the core plate are mainly known. In addition, elastic hollow annular expandable bodies fitted into an outer frame are arranged between filter plates, and the interior surrounded by the annular expandable bodies is used as a filtration chamber. No. 1268), the filter plate is covered with a U-groove rubber plate provided along the edge of one side to form an air packing, the air packing is inflated, and the inside surrounded by this air packing is used as a filtration chamber. There is one (Special Publication No. 45-7640).
Furthermore, an expandable sealing member is fixed around or overlapped with a flat filter plate made of a metal or synthetic resin net (Japanese Patent Application Laid-Open No. 61-61-1).
153111 and Japanese Unexamined Patent Publication No. 161112/1983).

[Problem to be solved by the invention]

However, in a compressed filter plate in which an elastic membrane is applied to the core plate surface of the filter plate, the elastic membrane sandwiched between the hard core plates is easily damaged by the tightening pressure of the filter plate or the pressure fluid pressure supplied and discharged. In addition, when the membrane fabric is repeatedly tightened, it becomes stretched and deforms to one side, and in particular, the overlapping position of the membrane discharge hole and the discharge hole of the filter plate core plate shifts, causing the hole to become clogged, preventing the discharge of filtrate. The problem was that abnormally high pressure was generated inside the filtration chamber. Furthermore, the pressurized chamber that accommodates the pressure fluid is large, and a large amount of pressure fluid must be supplied and discharged. Furthermore, the structure described in Japanese Patent Publication No. 47-1268 requires a complicated structure to assemble the inner expansion and contraction body so that it does not come off from the outer frame during use.
Also, its strength was not sufficient. Moreover, if the cake is tilted when being discharged, the expanding body tends to fall off from the outer frame. Further, in the method described in Japanese Patent Publication No. 45-7640, the presser frame plate is placed along the edge of the packing and bolted to the filter plate, so the holding edge of the packing is easily torn due to expansion and contraction of the packing. In addition, it is difficult to withstand high pressure and press the filter plate airtight around the entire circumference due to its strength. In addition, it is also possible to fix an inflatable sealing member around a net or the like or to overlap it.
In the devices described in JP-A No. 153111 and JP-A-61-161112, when the sealing member stretches, it tends to come off from the net, or the net deforms and falls into the filtration chamber, and when high pressure is applied, the filtration is interrupted. There is a risk of tearing the cloth. Therefore, an object of the present invention is to eliminate the above-mentioned drawbacks, and to provide a method for easily applying squeezing pressure by safely supplying and discharging pressure fluid to the clamping frame body of the filter plate of a single filter press. The purpose of the present invention is to provide a filter plate for a single filter press.

[Means to try to solve the problem]

The present invention provides a filter plate that performs filtration and compression dehydration by forming a peripheral tightening part from the filter wall part of the filter plate in series so that the tightening part can expand and contract. That is, the present invention provides a filter plate in which the peripheral edge is formed in a hollow elastic frame communicating with an external pressure supply source, and the center is formed in a plate-shaped filter wall continuously surrounded from the inside of the elastic frame. Then, the elastic frame is used as the tightening part of the filter plate, and the tightening part is overlapped with the tightening part of the adjacent filter plate, so that the central plate-shaped filter wall and the plate-shaped filter wall of the adjacent filter plate overlap. A filtration chamber is formed between the filtration chamber, a filtrate supply path for supplying the undiluted solution to be filtered from the outside into the filtration chamber, and a filtrate discharge path leading from the plate-shaped filtration wall surface to the outside. In the filter plate of a single filter press, the filter plate is covered with a filter cloth hung between the filter plate and the filter plate is tightened between a fixed plate on one side and a movable plate connected to a tightening device on the other side. Tightening parts 2 and 3 on the periphery of the plate 1
8 is a continuous wall 11, 11 part that divides the wall thickness of the central plate-shaped filter wall 3 from the thickness center to both sides, and a central plate-shaped filter wall 3 that is divided following the connecting walls 11, 11 parts on both sides. The frame-shaped tightening walls 10, 10 parts formed to be parallel to the above are further divided into the tightening walls 10, 10 parts on both sides, and have a width approximately equal to the width of the connecting walls 11, 11 parts. 8 parts of the outer circumferential wall formed of a series of walls on both sides having a hollow shape,
The filter plate of the single filter press is characterized in that an inlet 15 for supplying and discharging pressure fluid from the outside is provided in the outer circumferential wall 8.

[Effect]

A large number of filter plates are arranged such that the tightening portions on the peripheral edges of the filter plates are overlapped with the tightening portions of adjacent filter plates. Pressure fluid is supplied into the hollow chamber from the inlet on the outer circumferential wall of the elastic frame at the periphery of the filter plate, and the connecting walls on both sides of the tightening section are raised in the thickness direction, and the tightening walls on both sides following the connecting wall are made to stand up in the thickness direction. The filter plate extends in the thickness direction and comes into close contact with the tightening wall of the adjacent filter plate. Furthermore, the supply of pressure fluid is regulated, and a filtration chamber is formed between the filtration wall surrounded by the clamping part and the filtration wall of the adjacent filter plate. The rows of filter plates are tightened by a tightening device, and the stock solution supplied into each filter chamber is filtered by a filter cloth covering the filter wall surface. Next, the pressure fluid is gradually removed from the hollow chamber, while the clamping pressure of the filter plate is increased, and the clamping part is contracted under a constant pressure, and the filtered stock solution is further compressed. When the compression reaches its limit, the pressure in the hollow chamber is released, the filter plate rows are untightened, and the space between each filter plate is opened.

【Example】

The present invention will be explained using drawings which are examples.
The filter plate 1 of the single filter press according to the present invention has a filter wall 3 surrounded by a clamping part 2, which are superimposed on each other and arranged as shown in FIG. A filter cloth 4 is hung on the surface of the filter plate (Fig. 2).
One left end of this filter plate row is supported by a fixing plate 5, and the other end can be tightened from the right side by a tightening device 7 via a flexible plate 6. The filter plate clamping part 2 connects the connecting walls 11, 11 that divide the wall thickness of the filter wall 3 into both sides from the thickness center, the frame-shaped clamping walls 10, 10 that follow this, and both clamping walls in series. It consists of 8 parts of the outer peripheral wall and has a hollow chamber 9 inside. When a conduit is connected to the inlet 15 provided in the outer circumferential wall 8 and pressure fluid is supplied from the outside into the hollow chamber 9, the tightening part 2 expands into an approximately hexagonal shape as shown in the figure, and the frame-shaped tightening Attached wall 10, 10
The surface extends in the thickness direction of the filter plate, and the connecting walls 11,1
One part is inclined from the filter wall 3 and connected in series with the tightening walls 10, 10 parts (FIG. 3). Here, the thickness of the tightening walls 10, 10 is somewhat thicker than the wall thickness of the connecting walls 11, 11 and the outer circumferential wall 8 to increase the strength of surface pressure. Reference numeral 12 is a groove for supplying the stock solution to be filtered, and the filter plates are overlapped to form a passage for the stock solution in the groove 12. Also 13
indicates a filtrate discharge path that penetrates the periphery of the tightening part 2 from the inside to the outside (Figures 2, 3, and 6), 14 indicates a filtrate groove formed on the surface of the filter wall 3, and 15 indicates a pressure fluid discharge path. The inlet 16 is a stock solution supply pipe inserted into the stock solution supply groove 12. The above filter plates are arranged side by side as shown in Figure 1,
A filter chamber 17 is formed between a filter wall 3 of a filter plate and a filter wall 3 of an adjacent filter plate. A pressure fluid inlet 15 provided on the outer circumferential wall 8 of each filter plate and a water tank 18 outside the machine are connected by a conduit 20 which is divided into each hollow chamber 9 with a pump 19 connected therebetween. On the other hand, the movable plate side of the hydraulic cylinder of the tightening device 7 is connected to a hydraulic tank 23 by a conduit that passes through a switching valve 21 and then a hydraulic pump 22.
It is connected with. Further, the opposite side of the hydraulic cylinder is connected to a hydraulic tank 23 by a pipe passing through a switching valve 21, and a tightening device 7 for this pipe and a switching valve 2
A pressure electric transmitter 31 is attached to the side pipe branched from the middle of 1.
are connected. Further, a conduit 26 passing from the stock solution tank 24 to the stock solution pump 25 is separated from the middle and connected to each filtration chamber 17 . A stock solution supply pipe 16 is connected to the tip of the conduit 26 that is inserted into the stock solution supply groove 12 of the filter plate. Each filter plate has a pair of handles 27, 27 attached to the left and right outer sides of the tightening portion, and is placed on a side plate 30 extending between the front and rear machine frames 28, 29, so that the filter plate can be tightened or separated. Next, the filtration and squeezing operation will be explained using the above filter plate. A number of filter plates 1 are arranged between a fixed end plate 5 and a movable plate 6, and water from a water tank 18 (or compressed air from a compressed air tank) is passed through a pump 19 through a conduit 20 that is divided and connected to each filter plate. Supply into the hollow chamber 9 of the tightening part 2 at a constant pressure (first and third
figure). Next, the row of filter plates is tightened by the tightening device 7,
Ten clamping walls 10 of the clamping part 2 are brought into close contact with each other, and filtration chambers 17 are formed between adjacent filtering walls. When the tightening pressure of the tightening device 7 reaches a constant value, tightening is stopped, and then the undiluted solution is supplied from the undiluted solution tank 24 to each filtration chamber 17 through the conduit 26 by the pump 25. The stock solution is filtered by a filter cloth 4 placed on a filter plate, and the filtrate flows through a filtrate groove 14 on the filtration wall and is discharged from the filtrate discharge path 13 to the outside of the machine. When filtration has progressed to a certain extent, the supply of the stock solution is stopped and the row of filter plates is tightened again by the tightening device 7, and the pressure in the hollow chamber 9 in the tightening section 2 increases. At this time, the increased pressure is released by the safety valve 32, and the pressure in the hollow chamber 9 is always kept constant. Water is gradually discharged from the hollow chamber 9 to the outside, and the tightening part 2 is reduced in size, and the filtration chamber 1 is closed.
7 is compressed while being sealed (Fig. 4). The handle 27 slides outward across the top of the side plate 30,
The cake in the filtration chamber is also squeezed. The filtrate is similarly discharged to the outside from the discharge path 13. The pressure transmitter 31, the hydraulic pump 22, and the switching valve 21 are connected to a control board 33 outside the machine, and one end of the raw liquid conduit 26 is connected to the control board 33 via a raw liquid pressure switch 34 for operation. After tightening the rows of filter plates to a constant pressure value, the tightening is released to open the spaces between the filter plates and discharge the cake. According to the above-described embodiment, the connecting wall portions of the tightening portions of each filter plate are made to stand up at an angle to form a frame-shaped tightening wall 10.
Since the surfaces are stretched in close contact with each other and the filtration chamber is compressed during filtration compression, the filtration compression is extremely stable and the sealing between the filter plates is ensured. The filter plate shown in FIGS. 7 and 8 is a center feed type filter plate having a stock solution hole 35 approximately in the center of the filter wall 3. The stock solution is supplied to the filtration chamber 17 from a stock solution supply hole 36 located approximately in the center of the fixed end plate 5, and the front and back sides of the filter cloth 4 are connected in series around the stock solution supply hole 35 that penetrates the filter wall 3. . Further, the stock solution hole of the filter cloth is fixed around the stock solution hole 35 of the filtrate fixed to the fixing plate 5 with a stopper 37. FIG. 8 shows the tightening portion of the filter plate expanded in the thickness direction. Further, in FIG. 9, the tightening portion 38 is divided into two parts, and each side is formed with a wall thickness divided from the center of the thickness to both sides. Hollow chamber 3 in each tightening part on both sides
9, 39, into which pressure fluid is supplied and discharged. Although the volume within the hollow chambers 39, 39 is smaller than in the previous example, it is easier to adjust the extension of the tightening portion.
The filtrate discharge path 13 portion in this case is shown in FIG. The filter plate of the present invention is made of a rubber or plastic plate material, or a material laminated with cloth, glass fiber, etc. as a reinforcing layer. In addition, it is also possible to use a frame body sandwiched between the filter plates.

【Effect of the invention】

A predetermined amount of pressure fluid is supplied to the hollow chamber of the tightening part of each filter plate in which a large number of filter plates are arranged, the connecting wall part is raised, and the tightening part is extended in the thickness direction of the filter plate.
When a row of filter plates is tightened by a filter plate tightening device, a filter chamber having a thickness necessary for filtration is formed between the filter plates. Even if this row of filter plates is further tightened and the rising pressure is adjusted to narrow the filtration chamber and filtration is squeezed, the raw solution does not leak from between the frame-shaped tightening walls, and the seal between the filter plates is ensured. . Further, in the present invention, since the tightening portion and the filter wall portion are formed in a continuous manner, the filter wall and the tightening portion are unlikely to be torn, and can be safely tightened or unfastened. Further, the filtrate discharge passage is not clogged.

[Brief explanation of drawings]

Figure 1 is a side view of a single filter press with a large number of filter plates arranged in a longitudinal section, Figure 2 is a front view of the filter plate of a single filter press, and Figure 3 is an extended tightening part. 4 is an enlarged vertical sectional view of the same filter plate with the tightening portion compressed, FIG. 5 is a sectional view taken along the line A-A in FIG. 3, and FIG. A sectional view taken along the line B-B, FIG. 7 shows another example, and a side view showing a longitudinal section of filter plates of a single filter press in which a large number of sheets are arranged. FIG. 8 shows a filter plate of the single filter press shown in FIG. 7. 9 is a longitudinal sectional view of a filter plate of a single filter press showing still another example, and FIG. 10 is a sectional view taken along the line CC in FIG. 9. DESCRIPTION OF SYMBOLS 1... Filter plate, 2, 38... Tightening part, 3... Filtering wall, 4... Filter cloth, 8... Outer peripheral wall, 9, 39...
Hollow chamber, 10... Tightening wall, 11... Connecting wall, 13
...Filtrate drain, 15...Pressure fluid inlet, 17
...Filtering chamber, 18...Water tank.

Claims (1)

[Claims] 1. A filter plate whose periphery is formed in a hollow elastic frame that communicates with an external pressure supply source, and whose center is formed in a plate-shaped filter wall that is continuously surrounded from the inside of the elastic frame. The elastic frame is used as a tightening part of the filter plate, the tightening part is overlapped with the tightening part of an adjacent filter plate, and the central plate-shaped filter wall and the plate-shaped filter wall of the adjacent filter plate are connected to each other. A filtration chamber is formed between the filtration chamber, a filtrate supply path for supplying the undiluted solution to be filtered from the outside into the filtration chamber, and a filtrate discharge path leading from the plate-shaped filtration wall surface to the outside, and In the filter plate of a single filter press, which is covered with a filter cloth suspended between adjacent filter plates and tightened between a fixed plate on one side and a movable plate connected to a tightening device on the other side, The tightening parts 2, 38 on the peripheral edge of the filter plate 1 are connected to connecting walls 11, 11 that divide the wall thickness of the central plate-shaped filter wall 3 from the thickness center to both sides, and connecting walls 11, 11 on both sides. Next, it is divided into frame-shaped tightening walls 10, 10 parts formed to be parallel to the plate-shaped filter wall 3 in the center, and the tightening walls 10, 10 parts on both sides are further divided, and the above-mentioned connecting wall is formed. an outer circumferential wall 8 section formed by forming a series of walls on both sides having a width approximately equal to the width of the 11 sections; Entrance 15 for
A filter plate of a single filter press characterized by being provided with.