JP2013233480A - Filter press dehydrator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter press dehydrator provided with a compact hydraulic mechanism, capable of quickly opening or closing a filter plate and of securing sufficient clamping pressure at squeezing, and inexpensive in equipment cost.SOLUTION: A filter press dehydrator includes: a hydraulic pump 41 whose pressure is switchable in two stages in a low pressure zone; a flow channel-switching valve 47 for switching the flow of a hydraulic oil to either a first oil channel 45 for supplying the hydraulic oil to the advancing side port 35 of a hydraulic cylinder 30 via a backflow-preventing valve 44 or a second oil channel 46 for supplying to the retreating side port 36 of the hydraulic cylinder; and a hydraulic intensifier 60 set up via a pressure control valve 49 to a third oil channel 48 which is branched from the first oil channel at the upstream side of the backflow-preventing valve and joins together with the first oil channel at the downstream side. The dehydrator is composed such that each filter plate becomes in a closing state by the hydraulic oil supplied to the advancing side port via the first oil channel, the pressure control valve is activated by pressure increase in the first oil channel, and the hydraulic oil whose pressure is increased by the hydraulic intensifier is supplied to the advancing side port.

Description

  The present invention relates to a filter press dewatering apparatus.

  Conventionally, various sludge treatment processes such as dewatering sludge generated at water purification plants and sewage treatment plants and separating it into filtrate and cake, or solid-liquid separation processes required in the production process of carbon products, titanium products, etc. Filter press dehydrators are used in the field for solid-liquid separation.

  The filter press dewatering device includes a hydraulic cylinder that drives a plurality of filter plates forward and backward, and a hydraulic mechanism that supplies hydraulic oil to the hydraulic cylinders and switches each filter plate to a closed plate state or an open plate state. The hydraulic cylinder is driven by the hydraulic oil discharged from the hydraulic pump.

  The time required to open or close each filter plate is added to the cycle of pressing the object to be pressed into the filter chamber formed between the filter plates, the pressing process of the pressed object to be pressed, and the discharging process after pressing. Since it is a miscellaneous time to be performed, shortening of this time leads to improvement of the compression processing efficiency. If the pressure receiving area of the hydraulic cylinder is constant, the greater the amount of hydraulic fluid supplied from the hydraulic pump, the faster the hydraulic cylinder will advance and retract, and the time required for opening and closing will be reduced. Is done.

  In the squeezing step, the squeezed object pressed into each filter chamber is squeezed by feeding a squeezing fluid such as water between the filter plate and the diaphragm to expand the diaphragm. The filter plate is opened by the reaction force in the opening direction acting on each filter plate by the press-fitting of the pressurizing fluid, so that the object to be compressed and the filtrate are prevented from leaking and the closed plate-like body is held. The tightening pressure must be applied.

  Therefore, a large amount of discharge is required for the hydraulic pump in order to shorten the time required to open or close the filter plate, and a high discharge pressure is required to tighten the filter plate in the pressing process.

  Even if the hydraulic pump has a low discharge pressure, the clamping pressure required in the squeezing process can be secured by increasing the pressure receiving area of the hydraulic cylinder, but the discharge volume is reduced to reduce the time required to open or close the filter plate. If such a hydraulic cylinder and hydraulic pump are used, a large tank for storing a large amount of hydraulic oil is required, and a large hydraulic cylinder is attached to the filter press dehydrator. Therefore, the frame of the main body becomes large and the installation area becomes large.

  On the other hand, even if it is a hydraulic pump with a small discharge amount, if the pressure receiving area of the hydraulic cylinder is reduced, the time required to open or close the filter plate can be shortened, but in order to ensure the tightening pressure required in the squeezing process, It is necessary to be a hydraulic pump having a very high discharge pressure. Since such a hydraulic pump is very expensive, the equipment cost increases.

  In this way, it is extremely difficult to secure a strong clamping pressure in the squeezing process while shortening the time required to open or close the filter plate using a single hydraulic pump. In addition, it is necessary to combine a hydraulic pump with a high discharge pressure and a low discharge amount with a hydraulic pump with a low discharge pressure and a large discharge amount in order to quickly open and close the filter plate. Therefore, it was necessary to accept the high equipment cost of the hydraulic pump and to secure a large installation space.

  Therefore, Patent Document 1 includes a hydraulic piston cylinder that receives a hydraulic pressure from a hydraulic pump and moves a moving frame for filter plate pressing and tightening, and includes a hydraulic acting side of the hydraulic cylinder of the piston cylinder, one hydraulic pump, The basic tightening hydraulic system is connected to the base, and a hydroconverter that branches off at the hydraulic pump outlet side of the basic tightening hydraulic system and increases the pressure in parallel with the hydraulic pump system of the basic tightening hydraulic system is added. A filter press dewatering device having a filter plate tightening device provided with a tightening hydraulic system has been proposed.

  In this filter press dewatering device, the filter plate is quickly opened and closed by the hydraulic oil discharged from one hydraulic pump, and the pressure of the hydraulic oil discharged from the hydraulic pump is increased by a hydroconverter and filtered with a clamping pressure. It is comprised so that a board may be clamped and a pressing process may be performed.

Japanese Utility Model Publication No. 63-25104

  The filter press dewatering device described in Patent Document 1 is configured to ensure the tightening pressure of the filter plate by increasing the pressure of hydraulic oil discharged from a low-pressure and large-capacity hydraulic pump via a hydroconverter.

  However, in order to obtain a sufficient tightening pressure, it is necessary to use a hydroconverter with a large pressure increase rate, and there is no such hydroconverter with a large pressure increase rate that is widely used. As a result, the opening and closing time of the filter plate tended to be long.

  Also, in order to maintain the closed plate-like body against the reaction force acting on the filter plate during the squeezing process, a high pressure hose must be used for the hose connecting the output portion of the hydroconverter and the advance port of the hydraulic cylinder. In addition, complicated and expensive parts are required, and the device may be damaged when the pressure resistance is exceeded.

  An object of the present invention is to provide a filter press dewatering device that can quickly open and close a filter plate and can secure a sufficient tightening pressure at the time of squeezing, and has a low-cost equipment and a compact hydraulic mechanism. .

  In order to achieve the above-mentioned object, the filter press dewatering device according to the present invention is characterized in that a hydraulic cylinder that drives a plurality of filter plates forward and backward as described in claim 1 of the claims, and the hydraulic cylinder A hydraulic press mechanism that supplies hydraulic oil to each of the filter plates to switch between a closed plate state and an open plate state, wherein the hydraulic mechanism applies pressure in a low pressure region. A hydraulic pump that can be switched to a plurality of stages, and a first oil passage that supplies hydraulic oil discharged from the hydraulic pump to an advancing side port of the hydraulic cylinder or a second oil passage that supplies a retreating side port of the hydraulic cylinder A flow path switching valve for switching to any one of the above, a hydraulic pressure intensifier installed via a pressure control valve in a third oil path that branches off from the first oil path and merges with the first oil path on the downstream side; Including the first oil passage Each of the filter plates is closed by the hydraulic oil supplied to the advancing side port via the first oil passage, and the pressure control valve is operated by increasing the pressure in the first oil passage, and the pressure is increased by the hydraulic pressure intensifier. The hydraulic oil thus supplied is configured to be supplied to the advancing side port.

  Prior to the press-fitting process of the object to be compressed, when the low-pressure hydraulic oil discharged from the hydraulic pump is supplied to the advance port of the hydraulic cylinder via the flow path switching valve and the first oil passage, the hydraulic cylinder is driven to advance. Thus, each filter plate is switched from the open plate state to the closed plate state. When the filter plate is switched to the closed plate state and the oil amount decreases, the discharge pressure of the hydraulic pump increases, and when the pressure exceeds the operating pressure of the pressure control valve, the operating oil flows from the first oil passage into the third oil passage, The hydraulic oil sufficiently boosted via the hydraulic pressure intensifier joins the first oil passage and is supplied to the advance port of the hydraulic cylinder, and a tightening pressure is applied to the filter plate in the closed plate state.

  When the squeezing process is completed and the flow path switching valve is switched, the low-pressure hydraulic oil discharged from the hydraulic pump is supplied to the retraction side port of the hydraulic cylinder via the flow path switching valve and the second oil path, and the hydraulic cylinder Are retired and each filter plate is changed from the closed plate state to the open plate state.

  In this way, by combining a hydraulic pump and a pressure intensifier that can switch the pressure in multiple stages in the low pressure range with a pressure control valve, the filter plate can be opened and closed quickly, and sufficient clamping pressure can be secured during squeezing. Thus, a filter press dewatering apparatus having a compact hydraulic mechanism with a low equipment cost can be realized.

  In the second feature configuration, as described in claim 2, in addition to the first feature configuration described above, the hydraulic pressure intensifier is attached to a manifold block in which the first oil passage and the third oil passage are formed. The output port of the hydraulic pressure intensifier is directly connected to the input portion on the pressure increase side of the third oil passage, and the output portion of the first oil passage and the advance side port of the hydraulic cylinder are directly connected. is there.

  The output portion of the first oil passage formed in the manifold block is directly coupled to the advance port of the hydraulic cylinder. By forming the pressure water output from the hydraulic pressure intensifier or the oil passage to which the tightening pressure is applied in the manifold block, a high pressure hose is not required. Therefore, there is no risk of damage to the hose. Moreover, it can comprise compactly by connecting directly, without using a hose.

  In the third feature configuration, as described in the third aspect, in addition to the first or second feature configuration described above, the hydraulic pressure intensifier is slid in a cylinder having a large diameter and a cylinder having a different diameter. And the magnification of the hydraulic oil of the hydraulic pressure intensifier is set depending on the diameter of each piston.

  According to the above-described configuration, a desired pressure increase rate can be obtained based on the diameters of the pistons corresponding to the large and small cylinders having different diameters.

  In the fourth feature configuration, as described in claim 4, in addition to any of the first to third feature configurations described above, a branch portion of the first oil passage, The backflow prevention valve is provided between the junctions.

  According to the above-described configuration, when the hydraulic oil joins the first oil passage and is supplied to the advance port of the hydraulic cylinder, and tightening pressure is applied to the filter plate in the closed plate state, backflow prevention is performed in the first oil passage. Since the valve is provided, the pressurized hydraulic oil does not flow from the third oil passage to the upstream side of the confluence of the first oil passage, and can effectively apply the tightening pressure to the filter plate, The squeezing process is performed smoothly.

  Further, when the low pressure hydraulic oil is supplied to the retraction side port of the hydraulic cylinder through the flow path switching valve and the second oil passage, and each filter plate is switched from the closed plate state to the open plate state, the advance side port of the hydraulic cylinder Since the hydraulic oil discharged from the oil flows upstream of the first oil passage through the backflow prevention valve, the hydraulic oil does not flow into the third oil passage.

  In the fifth feature configuration, as described in claim 5, in addition to the fourth feature configuration described above, the first oil passage is operated at a predetermined tightening pressure or more on the downstream side of the check valve. It is in the point connected to the 2nd oil way through a relief valve to do.

  In the pressing step, pressure in the opening direction acts on the filter plate by the pressing fluid. In order to maintain the closed plate-like body against this reaction force, it is necessary to apply a large clamping pressure to the filter plate with hydraulic oil. If this pressure rises abnormally, there is a risk of damage to the hydraulic mechanism and the hydraulic cylinder including the parts provided in the oil passage. Even in such a case, when the pressure exceeds a predetermined tightening pressure, the relief valve is opened and the hydraulic oil in the first oil passage is bypassed to the second oil passage, so that each part is not damaged. The predetermined tightening pressure may be set to a value higher than at least the normal tightening pressure.

  In addition to the second feature configuration described above, the sixth feature configuration is formed in a lid body in which the advance side port of the hydraulic cylinder is screwed to the end of the cylinder, as described in claim 6. A mounting hole for bolting a bracket that supports the hydraulic pressure intensifier is formed around the advancing side port.

  If the internal thread formed on the inner peripheral surface of the annular end of the cylinder and the external thread formed on the circumferential part of the lid are screwed together, the lid itself is formed by the screws formed on the cylinder and the lid. Can be firmly attached to the cylinder, and can withstand high internal pressure. And what is necessary is just to attach the bracket which supports a hydraulic pressure intensifier to such a cover body.

  As described above, according to the present invention, a filter press dewatering device having a compact hydraulic mechanism that can quickly open and close the filter plate and can secure a sufficient tightening pressure during squeezing, has a low equipment cost, and is compact. Can now be offered.

Schematic of filter press dewatering device according to the present invention Illustration of hydraulic mechanism Illustration of hydraulic pressure intensifier It is explanatory drawing of the principal part of a hydraulic mechanism, Comprising: (a) is a top view, (b) is a front view, (c) is a left view, (d) is a right view It is explanatory drawing of a bracket, (a) is a top view, (b) is a rear view, (c) is a left side, (d) is a front view (A) is explanatory drawing of a cylinder, (b) is a side view of a cover, (c) is a front view of a cover

The filter press dewatering device according to the present invention will be described below.
As shown in FIG. 1, the filter press dewatering device 10 allows a plurality of filter plates 20 to move between a closed plate state and an open plate state on a side frame 13 installed between the left frame 11 and the right frame 12. It is arranged. Each filter plate 20 is pushed in the direction of the right frame 12 by the rod 33 of the hydraulic cylinder 30 being advanced by the hydraulic oil discharged from the hydraulic pump 41, and shifts to the closed plate state. When the rod 33 is driven to retreat, it shifts to an open plate state separated from each other.

  Between each filter plate 20, an endless filter cloth 14 supported by the support mechanisms 7 and 8 so that the filter surfaces face each other is arranged in the vertical direction. In the closed state of each filter plate 20, the slurry as the object to be treated is press-fitted into the filtration chamber formed in the space defined by the filter cloth 14 sandwiched between the filter plates 20, and the filter plate 20 is provided in that state. By expanding the diaphragm 21, a pressing process is performed in which the slurry is solid-liquid separated by the filter cloth 14. Thereafter, when each filter plate 20 is shifted to the open plate state, the dehydrated cake is peeled off from the filter cloth 14.

  Thus, the filter press dehydrator 10 repeats the opening and closing of the filter plate 20 and the press-fitting, pressing and discharging of the object to be compressed in accordance with a sequence set in advance on a control panel (not shown) to perform solid-liquid separation of the object to be compressed. It is configured to do it automatically.

The configuration of each part of the filter press dewatering device 10 will be described in detail.
A pair of side frames 13 is constructed between the left frame 11 and the right frame 12. A plurality of filter plates 20 are arranged on the side frame 13 so as to be slidable in the direction of the left frame 11 and the right frame 12.

  The filter plate 20 is provided with an upper roller 7 and a lower roller 8 as support mechanisms. The endless filter cloth 14 is stretched in the vertical direction between the adjacent filter plates 20 by the upper roller 7 and the lower roller 8. When the filter plate 20 shifts to the closed plate state, the space defined by the filter cloth 14 becomes the filtration chamber.

  A driving roller 15 for feeding out the filter cloth 14 is disposed on the upper frame 19 above the left frame 11 and the right frame 12, and a cleaning mechanism 16 for cleaning the filter cloth 14 after solid-liquid separation is disposed downstream of the drive roller 15. And a meandering mechanism 17 for applying a predetermined tension to eliminate bending of the traveling filter cloth 14 and a pair of rollers sandwiching the filter cloth 14 are moved to the left and right in the traveling direction of the filter cloth to correct meandering. A meandering correction mechanism 18 is provided. A guide roller is provided near the upper roller 7 for guiding the filter cloth 14 so as not to contact the filter plate 20 when the filter plate 20 is open. When the drive roller 15 is driven with each filter plate 20 open, the filter cloth 14 travels between the filter plates 20.

  A diaphragm 21 is attached to one side of each filter plate 20. A pressure water supply path (not shown) for supplying pressure water between the filter plate 20 and the diaphragm 21 is provided below each filter plate 20. In the closed state of each filter plate 20, each diaphragm 21 sandwiches the filter cloth 14 with the back surface of the adjacent filter plate 20.

  The right frame 12 is provided with a slurry supply port 23 for supplying a slurry that is an object to be squeezed into the filtration chamber, and a filtrate discharge port 24 for discharging the filtrate that has been solid-liquid separated by a filter cloth in the pressing step.

  Each filter plate 20 is configured so that through holes formed in the thickness direction of each filter plate 20 communicate with each other in a closed plate state, and each filtration chamber is filled with slurry from the slurry supply port 23 through the through holes. Is done. In this state, when pressure water is supplied from the pressure water supply path, the diaphragm 21 attached to the filter plate 20 expands to the filtration chamber side, and the slurry press-fitted into the filtration chamber partitioned by the filter cloth 14 is squeezed. . The filtrate separated by solid and liquid by the filter cloth 14 is discharged from the filtrate discharge port 24, and when the hydraulic cylinder 30 opens the filter plate 20, the dehydrated cake is discharged from between the filter plates 20.

  In FIG. 1, the left end filter plate 20 is connected to a pressing member 34 provided at the tip of a rod 33 of the hydraulic cylinder 30, and the right end filter plate 20 is connected to the right frame 12. Each filter plate 20 is provided with a pair of engaging pins projecting sideways at an upper and lower position that does not interfere with the side frame 13, and the engaging pins of a pair of adjacent filter plates 20 are connected to each other (not shown). ) Is engaged by a long hole formed in the). When the left end filter plate 20 moves in the direction of the right frame 12 by the advance drive of the rod 33 of the hydraulic cylinder 30, the filter plate 20 sequentially moves in the right direction accordingly, and by the retraction drive of the rod 33 of the hydraulic cylinder 30, When the left end filter plate 20 moves in the direction of the left frame 11, the filter plate 20 is sequentially separated at a predetermined interval defined by the long hole of the connecting member.

  As shown in FIG. 1, the left frame 11 is provided with a hydraulic cylinder 30. The hydraulic cylinder 30 includes a cylindrical cylinder 31, a piston 32 that divides the space inside the cylinder 31 into two chambers, and a rod that has one end connected to the piston 32 and the other end extending outward from the end surface of the cylinder 31. 33 is provided.

  The cylinder 31 is formed with an advancing side port 35 and a retreating side port 36 to which hydraulic oil from the hydraulic pump 41 is supplied to each of the two chambers defined by the piston 32. The advancing side port 35 is formed at the center of the end surface of the cylinder 31 on the retracting side of the rod 33. The retraction side port 36 is formed on the side surface of the cylinder 31 on the advance side of the rod 33.

  When the hydraulic oil from the hydraulic pump 41 is supplied to the advance port 35, the piston 32 moves in the cylinder 31 and the rod 33 moves forward. When the hydraulic oil from the hydraulic pump 41 is supplied to the retraction side port 36, the piston 32 moves in the cylinder 31 and the rod 33 is retreated.

  As shown in FIG. 6A, a female screw 31a is formed on the inner periphery of the end portion of the cylinder 31 on the advancing side port 35 side. As shown in FIGS. 6B and 6C, the lid body 37 has a cylindrical portion 37a inserted through the cylinder and a flange portion 37b integrally formed. Around the cylindrical portion 37a, a female screw 31a of the cylinder 31 is provided. A corresponding male screw 37c is formed. An oil passage 38 communicating with the advancing side port 35 formed in the flange portion 37b is formed through the center of the cylindrical portion 37a. A plurality of mounting holes 39 for fastening a bracket for supporting the hydraulic pressure intensifier 60 (see FIGS. 2 and 3) are formed around the advance port 35 of the flange portion 37b. Eight mounting holes 39 are formed at intervals of 45 degrees on the circumference centering on the advancing side port 35. Such a lid 37 is screwed into the end portion of the cylinder 31 to close the end portion of the cylinder 31.

  The end portion of the hydraulic cylinder 30 is screwed through a screw hole formed in the annular end surface of the cylinder 31 and a screw insertion hole formed in the annular shape in the lid body. It may be configured to be fastened and fixed, or to be formed with a flange at the end of the cylinder and fastened with bolts and nuts.

  As shown in FIGS. 1 and 2, the hydraulic mechanism 40 includes a hydraulic pump 41, a hydraulic circuit 42 that supplies hydraulic oil discharged from the hydraulic pump 41 to the hydraulic cylinder 30, and a tank 43 that stores the hydraulic oil. Yes.

  The hydraulic pump 41 is a hydraulic pump capable of switching the pressure to a plurality of stages in a low pressure region. For example, a low pressure multi-flow rate with a discharge pressure of 3.5 MPa, a discharge amount of 28 L / min, a discharge pressure of 11 MPa, and a discharge amount of 18 L / min. It is composed of a variable pressure piston pump with two pressures and two flows that can be switched between a high pressure and a small flow rate. The discharge hydraulic pump 41 can switch the pressure and flow rate of the discharged hydraulic oil in a plurality of stages by switching the inclination of the swash plate by the discharge amount control mechanism 41a according to increase / decrease of the outlet pressure.

  The low pressure and high flow rate with a discharge pressure of 3.5 MPa and a discharge amount of 28 L / min and the high pressure and low flow rate with a discharge pressure of 11 MPa and a discharge amount of 18 L / min are examples, and the switching pressure is adjusted by the discharge amount control mechanism 41a. Thus, the discharge pressure, the discharge amount, and the combination thereof are configured to be variable within a range in which the electric motor does not overload.

  The expressions of low pressure (3.5 MPa) and high pressure (11 MPa) simply represent the relative level of the discharge pressure of the hydraulic pump, and both belong to the low pressure range as compared with the clamping pressure of 70 MPa in the pressing process. The discharge pipe of the hydraulic pump 41 is provided with a pressure gauge 50.

  The hydraulic circuit 42 is a first oil passage 45 that supplies hydraulic oil discharged from the hydraulic pump 41 in a state of low pressure and high flow rate to the advancing side port 35 of the cylinder 31 via a pilot check valve 44 as a backflow prevention valve. A flow path switching valve 47 for switching to any one of the second oil passages 46 to be supplied to the retreat side port 36 of the cylinder 31, and a first oil on the downstream side after branching from the first oil passage 45 upstream of the pilot check valve 44. A third oil passage 48 that joins the passage 45 includes a hydraulic pressure intensifier 60 that is installed via a sequence valve 49 as a pressure control valve.

  The pilot check valve 44 uses the pressure of the hydraulic oil in the second oil passage 46 as a pilot pressure, and is released when the pilot pressure exceeds a predetermined pressure so that the hydraulic oil in the first oil passage 45 flows backward. It is configured.

  The first oil passage 45 is provided with a pressure gauge 52 for detecting an abnormal high pressure (70 MPa), and a start pressure (45 MPa) and a stop pressure (50 MPa) of the hydraulic pump 41 when the filter plate 20 is tightened. A pressure gauge 51 for detection is provided.

  The second oil passage 46 is provided with a pressure gauge 53 for detecting the backward end of the cylinder.

  The first oil passage 45 is connected to the second oil passage via the relief valve 54 on the downstream side of the pilot check valve 44. The relief valve 54 is set to open when the pressure in the first oil passage 45 is equal to or higher than a predetermined tightening pressure, for example, 70 MPa or higher.

  The sequence valve 49 provided in the third oil passage 48 is set to open when the pressure in the first oil passage 45 becomes 10 MPa or more.

The hydraulic pressure intensifier 60 will be described with reference to FIG.
The hydraulic pressure intensifier 60 is a mechanism including large and small cylinders 61 and 62 having different diameters, pistons 63A and 63B that slide in the respective cylinders 61 and 62, and a single rod 63C that couples the pistons 63A and 63B. And a mechanical valve 64 and a direction switching valve 65. The cylinder 61 is divided into two chambers 61A and 61B by the piston 63A. The cylinder 62 is divided into two pressure chambers 62A and 62B by the piston 63B. The piston 63B is formed with an oil passage 66 that allows the pressure chambers 62B and 62A in the cylinder 62 to communicate with each other. The magnification of the hydraulic oil pressure increase in the hydraulic pressure intensifier 60 depends on the diameters of the pistons 63A and 63B. Specifically, it is proportional to the pressure receiving area ratio of each piston. In the present embodiment, the pressure receiving area ratio of the pistons 63A and 63B is set so that the hydraulic oil supplied to the hydraulic pressure intensifier 60 is increased by six times and discharged.

  The operation of the hydraulic pressure intensifier 60 will be described. First, when the sequence valve 49 is opened, the hydraulic oil in the first oil passage 45 is supplied from the input port 60A to the pressure chamber 61A. The hydraulic oil supplied to the pressure chamber 61A pressurizes the piston 63A in the right direction. Then, the pistons 63A and 63B and the rod 63C move to the right, and pressurize and compress the hydraulic oil in the pressure chamber 62B. At this time, the check valve 68 is in a closed state. The check valve 67 is opened by receiving the pressure of the hydraulic oil in the pressure chamber 62B, the hydraulic oil in the pressure chamber 62B is supplied to the pressure chamber 62A via the oil passage 66, and the hydraulic oil that has entered the pressure chamber 62A is supplied. It is discharged from the output port 60B.

  Eventually, when the pistons 63A and 63B and the rod 63C reach the rightmost position of the stroke, the mechanical valve 64 is activated, and hydraulic oil is supplied from the input port 60A to the pilot valve of the direction switching valve 65, and the direction switching valve 65 is Switch. When the direction switching valve 65 is switched, the mechanical valve 64 operates again and returns to the initial state.

  By the operation of the direction switching valve 65, the hydraulic oil is supplied from the input port 60A to the pressure chamber 61B. The hydraulic oil supplied to the pressure chamber 61B pressurizes the piston 63A in the left direction. Then, the pistons 63A and 63B and the rod 63C move to the left, and the hydraulic oil in the pressure chamber 62A is pressurized and compressed. At this time, the check valve 67 is closed and the hydraulic oil in the pressure chamber 62A is discharged from the output port 60B. Since the pressure chamber 62B has a negative pressure, the check valve 68 is opened and the hydraulic oil in the pressure chamber 61A is sucked into the pressure chamber 62B.

  Eventually, when the pistons 63A, 63B and the rod 63C reach the leftmost position of the stroke, the mechanical valve 64 and the direction switching valve 65 are operated, and the hydraulic oil from the input port 60A is supplied to the pressure chamber 61A. Return. In this way, the hydraulic pressure intensifier 60 can discharge high-pressure hydraulic oil in one-way reciprocating path and return path of the pistons 63A and 63B and the rod 63C, and therefore, unlike a single-acting type such as a general water gun type, the discharge pulsation Therefore, continuous discharge can be performed. The excess hydraulic oil in the hydraulic pressure intensifier 60 is supplied to the second oil passage 46 from the output port 60C via the check valve 55 and returned to the tank 43.

  Based on a preset program, a control panel (not shown) feeds / stops the electric motor to drive / stop the hydraulic pump 40, or energizes / stops the solenoid of the direction switching valve 47 to perform direction switching control. Or the slurry supply control of the filter press dehydrator 10, the running control of the filter cloth 14, and the alarm notification control based on the signals of the pressure gauges of the hydraulic mechanism 40.

  The operation at the time of transition of the filter plate 20 to the closed plate state will be described below. The solenoid of the flow path switching valve 47 is energized to switch the valve, and the discharge side of the hydraulic pump 41 and the first oil path 45 are connected.

  First, when the hydraulic pump 41 discharges hydraulic oil at a low pressure and a high flow rate (discharge pressure 3.5 MPa, discharge amount 28 L / min), the hydraulic oil is supplied to the advancing side port 35 via the first oil passage 45. Then, the rod 33 of the hydraulic cylinder 30 is driven to advance, and each filter plate 20 moves in the closing direction.

  When each filter plate 20 is pushed into a closed plate state, the internal pressure of the first oil passage 45 rises, and when it exceeds a predetermined switching pressure set in advance, the discharge amount control mechanism 41a of the hydraulic pump 41 is activated, The discharge state of the hydraulic oil of the hydraulic pump 41 is switched to a high pressure and low flow rate (discharge pressure 11 MPa, discharge amount 18 L / min).

  The internal pressure of the first oil passage 45 is further increased by the high-pressure and small-flow hydraulic fluid discharged from the hydraulic pump 41, and when the pressure reaches 10 MPa, the sequence valve 49 is opened and the hydraulic oil is supplied to the hydraulic pressure intensifier 60. The filter plates 20 that have been moved to the closed plate state are further tightened by the hydraulic oil that has been increased to a maximum of 66 MPa by the hydraulic pressure intensifier 60.

  In a state where each filter plate 20 in the closed plate state is tightened, slurry is supplied to the filtration chamber partitioned by the filter cloth 14 sandwiched between the filter plates 20 as described above, and the diaphragm 21 is expanded to expand the inside of the filtration chamber. A pressing process for pressing the slurry is performed. Since pressure sufficient to withstand the internal pressure of the filtration chamber is applied by the pressure intensifier 60, slurry and filtrate do not leak from between the filter plates 20 in the closed plate state in the slurry pressing step.

  At this time, the reaction force from the filter plate 20 is applied to the rod 33 of the hydraulic cylinder 31, and the pressure of the hydraulic oil in the first oil passage 45 is increased from the pressure discharged from the hydraulic pressure intensifier 60. When this pressure is 70 MPa or more, the relief valve 54 is opened, and hydraulic oil can be released to the second oil passage 46. When the pressure gauge 52 detects this abnormal high pressure, the control panel issues an alarm based on the detection signal.

  Next, the operation | movement at the time of transfer to the open plate state of the filter plate 20 is demonstrated. After the slurry pressing step is performed for a predetermined time, flushing is performed in which the slurry supplied from the slurry supply port 23 remaining in the through hole of each filter plate 20 is removed by air blowing.

  When flushing is completed, the solenoid of the flow path switching valve 47 is energized to switch the valve, the discharge side of the hydraulic pump 41 and the second oil path 46 are connected, and the working oil is retreated via the second oil path 46. 36. Then, the rod 33 of the hydraulic cylinder 30 is driven to retreat and move in the direction in which each filter plate 20 opens. In this case, the discharge state of low pressure and high flow rate may be set from the beginning, or the discharge amount control mechanism 41a of the hydraulic pump 41 is operated, and the discharge state of the hydraulic oil of the hydraulic pump 41 is high pressure and low flow rate (discharge pressure 11MPa, discharge amount). 18 L / min) may be switched to a low pressure and high flow rate (discharge pressure 3.5 MPa, discharge amount 28 L / min).

  When each filter plate 20 is pushed into an open plate state, the internal pressure of the second oil passage 46 increases, and when the pressure gauge 53 detects a predetermined pressure (5 MPa) set in advance, the solenoid of the flow path switching valve 47 is turned off. The operation at the time of transition to the closed plate state of the filter plate 20 is started again after switching to neutral and after washing. The end of the rod 33 may be detected by a switch or a sensor.

  As each filter plate 20 is opened, the dewatered cake is discharged from each filter chamber. When a belt conveyor mechanism that conveys the dewatered cake discharged below each filter plate 20 of the filter press dewatering device 10 is disposed, when the dewatered cake is discharged from between the filter plates 20 in a short time, There is a possibility that a load is applied to the conveyor belt, which may cause poor transport of the dewatered cake and failure of the belt conveyor mechanism. Since the opening / closing speed of each filter plate 20 can be adjusted by changing the discharge state of the hydraulic oil by the discharge amount control mechanism 41a of the hydraulic pump 41, the discharge timing of the dewatered cake discharged from between the filter plates 20 is adjusted. can do.

  As described above, the filter press dewatering device 10 repeatedly executes a series of cycles of opening / closing of each filter plate 20 and press-fitting, squeezing and discharging of the slurry based on a program preset in the control panel.

  In such a series of cycles of slurry squeezing, the time taken to open and close each filter plate 20 is a miscellaneous time, so by supplying a large amount of hydraulic oil from the hydraulic pump 41 to the hydraulic cylinder 30, The operating speed of the hydraulic cylinder 30 can be increased to shorten the opening / closing operation time of each filter plate 20.

  As described above, one hydraulic pump 41 quickly opens and closes each filter plate 20 in the discharge state of low pressure and high flow rate, and the hydraulic oil in the low pressure range but discharge state of high pressure and low flow rate is hydraulic pressure booster. The pressure can be increased at 60 and the filter plates 20 can be tightened in the pressing process.

  By the way, the tank 43 provided in the filter press dewatering device 10 and the flow path switching valve 47 provided in the hydraulic circuit 42 are connected to the hydraulic pump 41 and unitized to constitute a pump unit 69. On the other hand, the pilot check valve 44, the first oil passage 45, the second oil passage 46, the third oil passage 48, the sequence valve 49, the hydraulic pressure intensifier 60, each pressure gauge, excluding the passage switching valve 47 in the hydraulic circuit 42. 51 to 53, the relief valve 54, and the check valve 55 may be integrated.

  As shown in FIGS. 2 and 4 (a) to 4 (d), the hydraulic pressure intensifier 60 is attached to the manifold block 70 in which the first oil passage 45, the second oil passage 46, and the third oil passage 48 are formed. The output port 60B of the hydraulic pressure intensifier 60 and the third oil passage 46 are directly connected. Further, the manifold block 70 includes a pilot check valve 44, a sequence valve 49, a hydraulic pressure intensifier 60, pressure gauges 51 to 53, a relief valve 54, and a check valve 55 formed in the first oil passage 45, respectively. The second oil passage 46 and the third oil passage 48 are attached at appropriate positions.

  The input / output part 69A of the pump unit 69 and the input / output part 45A of the first oil passage 45, and the input / output part 69B of the pump unit 69 and the input / output part 46A of the second oil passage 46 are connected by hoses 71 and 72, respectively. ing. Further, the input / output part 46 B of the second oil passage 46 and the retraction side port 36 of the hydraulic cylinder 30 are also connected by a hose 73. In the present embodiment, the hydraulic oil that circulates in the hoses 71 to 73 has a discharge pressure of about 11 MPa at the maximum.

  The input / output part 45 B of the first oil passage 45 formed in the manifold block 70 and the advance port 35 of the hydraulic cylinder 30 are directly connected via a nipple 74. The input / output part 45B may be subjected to a pressure of 70 MPa at the maximum due to the pressure of the hydraulic oil increased to 66 MPa at the maximum by the hydraulic pressure intensifier 60 or the reaction force from the filter plate 20 in the pressing process. If a direct connection is made with a pressure hose, a pressure hose that can withstand a pressure of 70 MPa is not required. Since a hose is not used, the risk of breakage is reduced, and the path can be shortened to make it compact.

  A bracket 75 for attaching the manifold block 70 and the hydraulic pressure intensifier 60 to the lid of the cylinder 30 will be described. As shown in FIGS. 5A to 5C, the bracket 75 is welded to one surface of a disk member 76, for example, a plate member 77 having an L shape in front view. In the center of the disk member 75, an opening 78 is formed at a position corresponding to the input / output part 45B of the manifold block 70. Around the opening 75, four fan-shaped long holes 79 of 45 degrees along the circumferential direction are formed at equal intervals. A screw hole 76 a for fixing the manifold block 70 is formed around the opening 78. A screw hole 77 a for fixing the hydraulic pressure intensifier 60 is formed in the plate member 77.

  As described above, since the eight mounting holes 39 of the bracket 75 are formed at intervals of 45 degrees on the circumference around the advance port 35, the first oil passage 45 formed in the manifold block 70 is formed. With the output portion 45B directly connected to the advancing side port 35, the mounting posture is adjusted so that the mounting hole 39 formed in the lid body 37 can be viewed from the long hole 79 formed in the bracket 75, and the bracket 75 is appropriately Screw in a proper posture. At this time, no matter how the bracket 75 is rotated in the circumferential direction around the advancing side port 35, at least one of the eight mounting holes 39 is superimposed on each of the long holes 79. Can be attached.

  As described above, according to the filter press dewatering device of the present invention, it is possible to shorten the opening / closing operation time of each filter plate and to apply a predetermined tightening pressure when each filter plate is closed safely and reliably. Became.

  Each of the above-described embodiments is an example of the present invention, and the present invention is not limited by the description. Specific configurations of each part (for example, a filter cloth, a filter plate, a diaphragm, a slurry supply unit, a filtrate discharge) Needless to say, the structure and arrangement of the parts and the like, as well as the structure of the hydraulic circuit and the structure of various control valves incorporated in the circuit, etc. can be changed and designed as appropriate within the scope of the effects of the present invention. .

10: Filter press dewatering device 11: Left frame 12: Right frame 13: Side frame 14: Filter cloth 20: Filter plate 21: Diaphragm 23: Slurry supply port 24: Filtrate discharge port 30: Hydraulic cylinder 35: Advance side port 36 : Retraction side port 37: Lid 40: Hydraulic mechanism 41: Hydraulic pump 42: Hydraulic circuit 43: Tank 44: Pilot check valve 45: First oil path 46: Second oil path 47: Flow path switching valve 48: Third Oil passage 49: Sequence valve 50: Pressure gauge 51: Pressure gauge 52: Pressure gauge 53: Pressure gauge 54: Relief valve 60: Hydraulic pressure intensifier

Claims (6)

A hydraulic cylinder that drives a plurality of filter plates forward and backward,
A filter press dewatering device comprising a hydraulic mechanism that supplies hydraulic oil to the hydraulic cylinder and switches each filter plate to a closed plate state or an open plate state,
The hydraulic mechanism is
A hydraulic pump capable of switching the pressure to multiple stages in the low pressure range;
A flow path switching valve that switches the hydraulic oil discharged from the hydraulic pump to either a first oil path that supplies the advancing side port of the hydraulic cylinder or a second oil path that supplies the retreating side port of the hydraulic cylinder; ,
A hydraulic pressure intensifier installed via a pressure control valve in a third oil passage that branches off from the first oil passage and merges with the first oil passage on the downstream side;
Each filter plate is closed by the hydraulic oil supplied to the advancing side port via the first oil passage, and the pressure control valve is activated by increasing the pressure in the first oil passage, A filter press dewatering device configured to supply hydraulic oil pressure-intensified by a hydraulic pressure intensifier to the advancing side port.   The hydraulic pressure intensifier is attached to a manifold block in which the first oil path and the third oil path are formed, and an output port of the hydraulic pressure intensifier and an input portion on the pressure increase side of the third oil path are directly connected, The filter press dewatering device according to claim 1, wherein an output portion of the first oil passage and an advancing side port of the hydraulic cylinder are directly connected.   2. The hydraulic pressure booster includes large and small cylinders having different diameters and pistons that slide in the respective cylinders, and the magnification of the hydraulic oil of the hydraulic pressure booster is set depending on the diameter of each piston. Or the filter press apparatus of 2.   The filter press apparatus in any one of Claim 1 to 3 which has a backflow prevention valve between the branch part and the merge part of the said 3rd oil path of the said 1st oil path.   5. The filter press dewatering device according to claim 4, wherein the first oil passage is connected to the second oil passage via a relief valve that operates at a predetermined tightening pressure or more on the downstream side of the backflow prevention valve.   An advancing side port of the hydraulic cylinder is formed in a lid screwed to an end of the cylinder, and a mounting hole for fastening a bracket that supports the hydraulic pressure intensifier is formed around the advancing side port. The filter press dewatering device according to claim 2.

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