JP2015020114A - Slurry feeding system, slurry feeding method, and dehydration device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system for feeding slurry to a dehydration part of an electroendosmosis dehydrator capable of molding even such slurry as with unstable water content or characteristics into a more uniform sheet-like shape, and as a result, more effectively performing electroendosmosis dehydration.SOLUTION: A slurry feeding system includes: pressure application means 22 configured to apply pressure to slurry 11; a plurality of slurry feed ports 31 arranged at intervals in a width direction on a downstream side of the pressure application means 22; and sheet molding means 41, 43, 44 capable of holding therebetween an entire line of the slurry 11 discharged from the plurality of slurry feed ports in the width direction on a downstream side of the plurality of slurry feed ports 31.

Description

  The present invention relates to a slurry supply system and method, and a dehydrator used when dewatering a slurry such as sludge generated from wastewater treatment facilities or the like and a hydrous intermediate produced in an industrial product production process by an electroosmotic dehydration method. .

  The electroosmotic dehydration method is a method of separating solids and water in a slurry such as sludge using the principle of electroosmosis. Specifically, when a direct current voltage is applied by sandwiching the slurry with an electrically conductive material such as metal, the solid matter whose surface is negatively charged is attracted to the anode side, and the positively charged moisture is attracted to the cathode side. Separation of solids and moisture proceeds.

  A feature of the electroosmotic dehydration method is that the slurry can be dehydrated to a lower water content (= mass of liquid in the slurry / mass of the entire slurry), for example, 70% or less. Therefore, it is often used when it is required to highly dehydrate the slurry. In addition, an electroosmotic dehydration method may be used after sludge generated at various wastewater treatment plants, waste treatment plants, etc. is dehydrated and reduced by mechanical dehydration methods such as centrifugation and filter press.

  For example, Patent Document 1 describes an electroosmotic dehydration apparatus that includes an anode-side rotary pressure drum and a cathode-side press belt that is superimposed on a filter belt and stretched around the pressure drum. Has been. Patent Document 2 describes a sludge dewatering device including an electroosmotic dehydrator as a secondary dehydrator.

  In the electroosmotic dehydration method, it is desirable that the slurry sandwiched between the anode and the cathode, for example, the drum and the belt, forms a thin and uniform layer. This is because if the slurry layer is too thick, the electrical resistance increases and the power consumption increases. In addition, even when the slurry has a non-uniform thickness and voids, the voids do not conduct electricity, so the electrical resistance increases and power consumption increases. However, the slurry to be treated is often not uniform in water content and properties, and it has been difficult to develop it into a thin and uniform sheet.

  In this regard, Patent Document 2 proposes cutting out sludge while stirring with a screw, forming the sheet into a sheet with a predetermined thickness by a pair of parallel rollers disposed below, and supplying the sheet to an electroosmotic dehydrator. ing. Moreover, in patent document 3, the electro-osmosis dehydrator which provides a cake pressing roll in the front position of a dewatering part at an appropriate interval above the filter cloth belt and supplies sludge cake with a uniform thickness to the dewatering part. Have been described.

Japanese Examined Patent Publication No. 3-46166 Japanese Patent No. 4651045 Japanese Utility Model Publication No. 6-15706

  However, the present inventors have found that even with the methods described in Patent Documents 2 and 3, there is still room for improvement in the uniformity of the slurry formed into a sheet.

  That is, in the method of Patent Document 2, the sludge that has not entered between the parallel rollers rolls on the rollers to form a dump, which prevents the newly supplied sludge from entering, and the sludge lump is greatly increased in a snowball style. It could happen. This is because if there is a part where the water content is low and the fluidity is impaired, the sludge is not smoothly sandwiched between the parallel rollers, or when the sludge is put on the rollers, a lump larger than the roller interval is formed. This happens due to the formation.

  When such a situation occurs, it is necessary to stop the operation of the dehydrator and allow the worker to break down the dumpling sludge and push it between the rollers. Or the problem that the uniformity of the sheet sludge supplied to a dehydrator is spoiled even if it does not stop operation.

  In addition, Patent Document 3 does not explain the method of introducing sludge onto the filter cloth belt, but simply controlling the amount of sludge introduced is due to the uneven moisture content and fluidity in the sludge. There are problems such as leaving voids even after passing through the pressing roll.

  The present invention has been made in consideration of the above points, and an object thereof is to propose a slurry supply system and method capable of forming into a more uniform sheet shape even if the water content and properties are not stable. To do. Another object of the present invention is to provide such a dehydrating apparatus.

  In order to solve the above problem, in the present invention, after the slurry is discharged in a streak shape from a plurality of slurry supply ports provided at intervals in the width direction, the slurry is formed into a sheet by a sheet forming unit.

  The slurry supply system of the present invention is a system for supplying slurry to a dehydrating part of an electroosmotic dehydrator, and is a pressure applying means for applying pressure to the slurry, and is located downstream of the pressure applying means, and is in the width direction. A plurality of slurry supply ports provided at intervals between the slurry supply ports and the plurality of slurry supply ports can be sandwiched between the plurality of slurry supply ports in the width direction of the slurry lines discharged from the slurry supply ports. Sheet forming means.

  Here, “downstream” is based on the flow of the slurry, and in the slurry supply system of the present invention, it means that the slurry flows in the order of the pressure applying means, the slurry supply port, and the sheet forming means. Here, the “width direction” refers to the width direction of the sheet-like slurry supplied to the dewatering unit.

  With this configuration, the slurry to which pressure is applied is divided and discharged from a plurality of supply ports, whereby the distribution in the width direction of the slurry supply amount becomes more uniform, by the sheet forming means sandwiching the entire width direction, The slurry can be formed into a more uniform sheet and supplied to the dewatering unit.

  In one aspect of the slurry supply system, the sheet forming unit is disposed upstream of the dewatering unit of the electroosmotic dehydrator, and is disposed at intervals above the belt wound around a plurality of rollers. A presser roll.

  Here, “upstream” is based on the slurry flow. The fact that the sheet forming means is provided upstream of the dewatering section means that the slurry that has passed through the sheet forming means subsequently enters the dewatering section. With this configuration, the slurry that is divided and discharged in the width direction is sandwiched between the belt and the pressing roll, is formed into a uniform sheet, and can enter the dewatering unit.

  In another aspect of the slurry supply system, the sheet forming unit includes a pair of forming rolls parallel to each other and spaced below the slurry supply port. Slurry streaks discharged from a plurality of supply ports can be formed into a sheet by passing between a pair of forming rolls and supplied to an electroosmotic dehydrator.

  The pressure applying means may be a pump that pumps the slurry. Thereby, a pressure can be simply applied to the slurry.

  Preferably, the slurry supply port is a cylindrical nozzle. Thereby, even if the fluidity of the slurry fluctuates, the influence on the discharge amount can be reduced, and the uniformity of the distribution of the discharge amount in the width direction is improved.

  Preferably, each of the slurry supply ports includes a valve for adjusting the discharge amount. As a result, the discharge amount distribution in the width direction can be adjusted more precisely.

  Preferably, the slurry supply system further includes a pressure gauge that detects a pressure applied to the slurry, and at least a water adding device for the slurry disposed upstream of the plurality of slurry supply ports. Thereby, even when the water content of the slurry fluctuates and the fluidity is lowered, the fluidity can be adjusted by adding water to the slurry as the pressure increases.

  Any of the above slurry supply systems may be a system for supplying sludge generated from wastewater treatment facilities. Such sludge has a particularly large effect obtained by the slurry supply system of the present invention because the moisture content and properties are not stable among various slurries.

  The slurry supply method of the present invention includes a step of applying pressure to the slurry, a step of discharging the slurry to which pressure has been applied in a stripe shape from a plurality of supply ports provided at intervals in the width direction, and a stripe shape. It includes a step of sandwiching the whole of the plurality of discharged slurry in the width direction and stretching it into a sheet, and a step of supplying the sheet-like slurry to a dehydrating unit of an electroosmotic dehydrator.

  By this method, by applying pressure to the slurry and discharging it from a plurality of supply ports, the distribution in the width direction of the supply amount is made more uniform, and the slurry is formed into a more uniform sheet shape. It can supply to a dehydration part.

  The dehydrator of the present invention has a slurry feeder and an electroosmotic dehydrator. The slurry feeder has a plurality of slurry supply ports provided at intervals in the width direction for discharging the slurry to which pressure is applied. The electroosmotic dehydrator includes an anode-side rotary pressure drum, a cathode-side belt wound around a plurality of rollers, and a dehydrating unit where the anode-side drum and the cathode-side belt face each other. An upstream of the dewatering unit has a receiving part for discharging slurry from the slurry supply port on the belt, and is provided between the receiving part and the dewatering part with a gap above the belt and the belt. And a thickness adjusting unit including a pressing roll.

  With this configuration, electroosmosis dehydration can be performed on a more uniform sheet-like slurry, so that dewatering efficiency can be improved.

  According to the slurry supply system, the slurry supply method, or the dehydration apparatus of the present invention, even a slurry whose water content and properties are not stable can be formed into a more uniform sheet and supplied to the dehydration unit.

It is a figure which shows the whole structure of 1st Embodiment. It is a figure which shows the sludge supply machine of 1st Embodiment. It is a figure which shows the whole structure of 2nd Embodiment. It is a figure which shows the apparatus of sludge supply experiment. It is a figure which shows the result of a sludge supply experiment. It is a figure which shows the sludge supply machine of 3rd Embodiment. It is a figure explaining the condition where the moisture content of the sludge stored by the hopper becomes non-uniform | heterogenous.

  A first embodiment of the present invention will be described with reference to FIGS. 1 and 2. 1st Embodiment processes the sludge produced from a wastewater treatment facility etc. as a slurry.

  First, based on FIG. 1, the whole structure of this embodiment and the flow of sludge are demonstrated. FIG. 1 shows a sludge dewatering device 10 and a sludge transport system 20. The sludge dewatering device 10 includes a sludge feeder 30 and an electroosmotic dehydrator 40.

  As the sludge 11 to be treated in this embodiment, sludge generated from various wastewater treatment facilities and waste treatment facilities can be used. When the sludge is biologically treated sludge, its moisture content is typically 97-99%. Moreover, you may use the sludge once dehydrated by other systems, for example, mechanical dehydration methods, such as centrifugation and a filter press. In that case, the moisture content of the sludge is typically about 82 to 86%.

  In FIG. 1, the sludge transport system 20 includes a hopper 21, a kneader 23 below the hopper 21, a pump 22 for pumping sludge under the kneader 23, and a transport pipe 26. The sludge 11 is temporarily stored in the hopper 21, kneaded by the kneader 23, and pumped by the pump 22 to the sludge feeder 30 through the transfer pipe 26.

  The sludge supply machine 30 has a plurality of sludge supply ports 31. The sludge pumped by the pump 22 is discharged from the plurality of sludge supply ports 31 in a string shape such as a string shape or a ribbon shape, and supplied to the electroosmotic dehydrator 40. Details of the sludge feeder will be described later.

  The electroosmotic dehydrator 40 includes an anode-side pressure rotary drum 42, an endless belt 43 wound around a plurality of rollers 45, and a portion of the belt 43 that overlaps the belt 43. And an endless filter 44. The sludge 11 from the sludge feeder 30 is discharged to the receiving portion 47, and then sandwiched between the downstream pressing roll 41, the filter 44, and the belt 43 to be formed into a sheet shape, and then the rotary drum 42, the filter 44, and the belt 43. Enters the opposite dewatering section 46. The sludge 11 is squeezed by the rotary drum 42 and the belt 43 in the dehydrating unit 46 and dehydrated by receiving an electroosmotic action. The thickness of the sludge sheet supplied to the dewatering unit 46 is 5 to 30 mm.

  Next, details of each part will be described.

  In the sludge transport system 20 of FIG. 1, once the sludge 11 is temporarily stored in the hopper 21, several advantages can be obtained. The advantage is that it can absorb the difference in the processing capacity of the former stage equipment and the latter stage electroosmosis dehydrator where sludge is generated by adjusting the operation time, and can be used as a buffer in case of any equipment trouble. However, when the sludge 11 is stored in the hopper 21, drying proceeds on the surface that comes into contact with air, and moisture in the sludge flows downward, so that the moisture content of the sludge tends to be uneven depending on the position in the hopper 21. Furthermore, if new sludge is sent from there to the previous stage, layers with different moisture contents will be stacked one above the other. When this state is schematically shown in FIG. 7, a portion 11 a having a low moisture content and a portion 11 b having a high moisture content are formed in the hopper 21. In such a state, even if the sludge is stirred and cut out, it becomes difficult to make the sludge properties uniform. Moreover, since sludges having different moisture contents are sequentially pumped, the moisture content of the sludge sent to the sludge feeder varies over time.

  The kind of the kneader 23 is not particularly limited, and a known one such as a rotating paddle or screw can be used. Further, sludge may be kneaded by a static mixer downstream of the pump 22. The type of the pump 22 is not limited, but it is always possible to continue to send a certain secured volume first, and it is suitable for transporting substances with high viscosity and low fluidity. A uniaxial pump such as a registered trademark) can be suitably used.

  FIG. 2 shows the configuration of the sludge feeder 30 together with a part of the electroosmotic dehydrator 40. In FIG. 2, the sludge supply machine 30 includes a header pipe 32 to which the sludge 11 pumped by the pump 22 arrives, and a plurality of sludge supply ports branched from the header pipe 32 and provided at intervals in the width direction. Nozzle 31. The nozzle 31 of FIG. 2 is a straight tube, and a pipe 35 branched from the header tube 32 is connected in the middle of the straight tube. Each nozzle 31 includes a discharge amount adjusting valve 33 and a lid 34 that can be opened and closed at the rear end.

  The form of the sludge supply port 31 is not particularly limited. The supply port 31 may be a nozzle as shown in FIG. 2 or a hole provided in the pipe wall of the header pipe 32. Various shapes such as a circular shape, an oval shape, a rectangular shape, and a slit shape can be adopted as the shape of the discharge section of the supply port 31. Preferably, the aspect ratio of the discharge cross section is close to 1. This is because the amount of sludge discharged from each supply port 31 does not vary depending on the position in the width direction. Preferably, the supply port 31 is a nozzle. This is because if the discharge resistance when the sludge passes through the supply port 31 is too small, the discharge amount is easily affected by the properties of the sludge such as the moisture content, and the balance of the discharge amounts from the plurality of supply ports 31 is likely to fluctuate. .

  The size of the sludge supply port 31 is not particularly limited, but it is preferable that the thickness of the discharged sludge is sufficiently smaller than the diameter of the pressing roll 41, specifically, the uppermost surface of the discharged sludge is the pressing roll 41. It is preferable that the position is lower than the center of rotation. More specifically, when the thickness of the discharged sludge is h, the radius of the pressing roll 41 is R, and the gap between the pressing roll 41 and the filter 44 is C, the relationship of h <R + C is established. preferable. This is because it is possible to suppress the discharge of a sludge lump that does not easily enter between the sheet forming means, that is, between the filter 44 and the pressing roll 41. In this embodiment, since the pressure is applied to the sludge, the sludge can be discharged without any problem even if the opening of the supply port 31 is small.

  The number of the sludge supply ports 31 can be determined according to the size of the equipment, the width of the sludge sheet supplied to the electroosmosis dehydration unit, the viscosity of the sludge, etc. The above is preferable. With a single supply port, even if a slit-shaped supply port is used, it is difficult to uniformly discharge sludge from its entire width. By providing a plurality of supply ports, sludge can be discharged to a preset position in the width direction, and the distribution of the sludge amount in the width direction can be made more uniform. According to the experiments by the inventors, good results were obtained by using three nozzles with a width of 500 mm and five nozzles with a width of 2000 mm.

  The interval between the sludge supply ports 31 is not particularly limited, but it is preferable that the sludge discharged from each supply port 31 is large enough to form an independent line. Even when the opening has a slit shape that is long in the width direction, the interval between the adjacent supply ports 31 is preferably larger than the short side or the short diameter of the opening.

  Each sludge supply port 31 is preferably provided with a discharge amount adjustment valve 33. Thereby, the distribution in the width direction of the amount of sludge supplied to the electroosmosis dehydration unit can be adjusted more closely. As the discharge amount adjusting valve, a known valve valve, needle valve, globe valve or the like can be used.

  In FIG. 2, an openable / closable lid 34 is provided at the rear end of the straight tubular nozzle 31. Accordingly, the lid 34 can be closed during operation, and the lid 34 can be opened during cleaning to easily clean the inside of the nozzle 31.

  Referring to FIG. 1, an electroosmotic dehydrator 40 includes an anode-side rotary drum 42, an endless belt 43 wound around a plurality of rollers 45, and a part of which overlaps with the belt 43. And an endless filter 44 wound around a roller 45. Here, the materials and structures of the rotary drum 42, the belt 43, and the filter 44 are not particularly limited, and known ones can be used.

  In FIGS. 1 and 2, the sludge 11 is discharged in a plurality of streaks from the sludge feeder 30 onto the filter 44 supported on the belt 43 by the receiving portion 47 of the electroosmotic dehydrator 40. Preferably, the sludge 11 is discharged near the pressing roll 41. If a nozzle is used as the supply port 31, sludge can be discharged closer to the pressing roll, which is also preferable in this respect.

  Downstream of the sludge receiving portion 47, the belt 43, the filter 44, and the press roll 41 disposed above the filter 44 with a space therebetween are entered, and are formed and stretched into a sheet shape. The

  The distance between the pressing roll 41 and the lower filter 44 and belt 43 can be adjusted. In the case where there are a plurality of press rolls 41, it is preferable to gradually narrow the interval in the sludge moving direction because the sludge enters smoothly and the sludge thickness can be determined at the position of the last press roll. .

  Preferably, at least one of the pressing rolls 41 has a driving device different from the belt 43 and the filter 44 so that the rotation speed can be controlled. By making the circumferential speed of the pressing roll 41 slightly larger than the linear speed of the filter 44, the sludge 11 can be sandwiched more strongly and smoothly.

  As described above, in the present embodiment, with reference to FIG. 1, the pump 22 that is a pressure application unit that applies pressure to the sludge 11, the nozzles 31 that are provided in plural in the width direction, and the electroosmotic dehydration The sludge supply system is constituted by the sheet forming means including the belt 43, the filter 44, and the pressing roll 41 of the machine 40. When the sludge 11 pumped by the pump 22 is divided in the width direction and discharged from the nozzle 31, the distribution of the sludge supply amount in the width direction can be made more uniform. As a result, the sludge can be supplied to the dehydrating unit 46 in a more uniform sheet form.

  Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, sludge generated from a wastewater treatment facility or the like is treated as a slurry. In FIG. 3, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG. The second embodiment is different from the first embodiment in that a pressure gauge 25 is provided at the outlet from the pump 22 and a water adding device 24 is provided in the kneader 23.

  Here, prior to the description of the second embodiment, an experiment conducted by the present inventors will be described. If the moisture content of the sludge changes, even if it is a slight change, the sludge fluidity may change greatly, causing a failure in supply. Therefore, the present inventors conducted an experiment for confirming the relationship between the moisture content of sludge and the supply trouble.

  FIG. 4 shows an experimental apparatus 50 used for the supply experiment. In the experiment, sludge obtained by dewatering sludge generated at a human waste treatment plant to a water content of about 82 to 86% by a centrifugal separation method was used. The experimental apparatus 50 uses a drum dryer. The experimental apparatus 50 includes a drum 62 having a diameter of 1000 mm and a width of 2000 mm, and two pressing rolls 61 a and 61 b provided above the drum 62 with a space therebetween. The sludge 11 pumped by a pump (not shown) was discharged from the nozzle 51 to the front of the pressing roll 61a. Nozzles 51 having an inner diameter of about 25 mm and a length of 200 mm were branched from the header pipe 52 and five nozzles were provided in the width direction. A pressure gauge (not shown) was provided at the outlet of the pump to measure the pump discharge pressure. The sludge 11 gradually shrinks in volume on the drum 62, but has a thickness of about 20 to 30 mm at the positions of the pressing rolls 61a and 61b. The roll 69 is disposed at a position opposite to the sludge traveling direction in order to prevent the sludge 11 that has not smoothly entered the holding roll 61a from spilling out.

  FIG. 5 shows the results of five experiments. Each experiment was run for about 6 hours on different days. The horizontal axis in the figure indicates the operation time from the start of the experiment, and the vertical axis indicates the pump discharge pressure at that time. The moisture content of sludge in each experiment varied in the range of 81.8% to 86.2%. In an experiment on May 12, when the moisture content was relatively high at 86.2%, the discharge pressure was stable at about 0.2 MPa or less. On the other hand, in the experiments on April 11, 13, 14, and 19 in which the moisture content was 85% or less, the discharge pressure was almost doubled to 0.4 MPa or more, and increased to 0.5 MPa at the maximum. In the experiment on April 13, the discharge pressure rapidly increased from 0.3 MPa in the initial operation to 0.4 MPa or more. Among the five experiments, in the experiments on April 11, 14, and 19, sludge clogging occurred at the position of the pressing roll 61b.

  As a result of this experiment, the pump discharge pressure increased greatly and supply failure occurred when the moisture content of the sludge decreased by only 1 to 2 points from the middle of the 80% range. However, the moisture content of the sludge often varies when it is supplied from the previous equipment as in this experiment, and even if a primary dehydrator is installed in the previous stage, the moisture content (%) of the sludge is It is difficult to control within the range of 1 to 2 points. Further, as described above, the moisture content of the sludge changes during storage in the hopper 21.

  In the second embodiment, referring to FIG. 3, by monitoring the pump discharge pressure with the pressure gauge 25, the water content of the sludge 11 is increased by the water adding device 24 when the discharge pressure rises suddenly or greatly. be able to.

  The pressure gauge 25 can be provided between the pump 22 and the sludge supply port 31. For example, it can be provided in the pump outlet, in the middle of the pipe 26 of the sludge conveyance system, in the header pipe 32 of the sludge feeder 30 and the like. Although the value measured differs depending on the location where the pressure gauge is provided, it is not always necessary to know the pressure value at a specific location for the purpose of this embodiment. Regardless of where the pressure gauge is installed, by recording the measured pressure value and the presence or absence of supply failure for a while, the relationship between the measured pressure value and the possibility of supply failure can be grasped for each device. . For example, in the case shown in FIG. 5, when the pump discharge pressure exceeds 0.3 MPa, water is added. Thus, by providing the pressure gauge 25, the pressure applied to the sludge can be detected directly or indirectly.

  The water adding device 24 can be provided upstream of the sludge supply port 31. For example, it can be provided in the kneading machine 23 at the lower part of the hopper, the pipe 26 of the sludge conveyance system, the header pipe 32 of the sludge supply machine 30, and the like. The water used for hydration does not necessarily need to be fresh water, and any water that does not adversely affect the sludge properties, such as sewage used for cleaning equipment to which sludge has adhered, may be used.

  With such a configuration, when the pump pressure rises, such as when a sludge having a low water content reaches the sludge supply port, it can be added to the sludge 11. As a result, it is possible to prevent the supply port 31 from being blocked or clogging at the pressing roll 41 after the supply and discharge. Moreover, even if it does not reach this obstacle, it can suppress that the uniformity of a sheet | seat is impaired by including the part where sludge is poor in fluidity | liquidity.

  In addition, adding water to sludge scheduled for dehydration is accompanied by energy loss. However, if the increase in water content (%) by only 1 to 2 points can prevent sludge supply problems to the subsequent electroosmosis dehydrator and decrease in efficiency of the electroosmosis dehydrator as a whole, It may lead to improvement of sludge treatment efficiency. In this regard, for example, the loss when the water content of the sludge is added by 2.2 points from the average of 84.0% of the experiment on April 14 to the average of 86.2% of the experiment on May 12 is as follows. Estimated. Assuming that the volume of sludge pumped and the mass of water removed by the electroosmosis dehydrator are constant, the sludge is 84% to 86.2% compared to the case where the sludge is dehydrated from 84% to 68%. As a result, the treatment capacity was reduced by 15%, and the water content of the sludge after dehydration was increased by 4 points from 68% to 72%. Sludge having a moisture content of about 70% originally has no fluidity, and such a change in moisture content does not cause a problem in operating the sludge transporting equipment after dehydration. On the other hand, the merit of adding water is that the possibility of clogging at the supply port and the pressing roll, the accompanying stoppage of the apparatus, cleaning work, increased burden on workers, risk of accidents, and the like can be reduced.

  Next, a third embodiment of the present invention will be described with reference to FIG. The third embodiment also treats sludge generated from a wastewater treatment facility or the like as a slurry. In FIG. 6, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG. In 3rd Embodiment, the sheet forming means is provided with a pair of forming rolls 71, 71 arranged below the sludge supply port 31 with a space therebetween.

  The pair of forming rolls 71, 71 are arranged horizontally in parallel with the width direction. The sludge discharged from the sludge supply port 31 is formed into a sheet shape by the forming rolls 71 and 71 and supplied to the electroosmotic dehydrator 40.

  With this configuration, the pressure-fed sludge 11 is divided in the width direction and discharged from the nozzle 31, so that it is possible to suppress the discharge of sludge lump that is difficult to enter between the forming rolls 71, 71. The distribution of the sludge supply amount in the width direction can be made more uniform. As a result, sludge can be supplied to the electroosmotic dehydrator 40 in a more uniform sheet form.

  The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the technical idea.

  For example, although the case where the sludge produced from a wastewater treatment facility etc. is processed as a slurry was demonstrated in the said embodiment, the slurry made into the object of this invention is not limited to this. The present invention can also be used for the treatment of sludge generated in various processes such as a human waste treatment plant, a sewage treatment plant, a paper mill, and a smelting plant in the mining industry even when sludge is targeted. Furthermore, the present invention is intended for slurries other than sludge, separation / extraction of useful components in the food manufacturing field, filtration / squeezing to recover soy sauce, etc., separation / collection of polymer particles in the polymer manufacturing field, etc. It can be used in the manufacturing process.

  In the above embodiment, an example in which a pressure pump such as a single-shaft pump is used as a means for applying pressure to sludge has been shown. Alternatively, air pressure is applied to the hopper using a compressor or the like, and sludge is pneumatically fed. Good.

  Further, in the electroosmotic dehydrator of the above embodiment, referring to FIG. 1, a belt 44 and a separate filter 44 are used. Therefore, the sludge 11 is discharged onto the belt 43 through the filter 44 superimposed on the belt 43. However, the filter may be omitted when a belt having functions of both a belt and a filter is used. For example, Japanese Patent Application Laid-Open No. 2011-177692 discloses an electroosmotic dehydrator that omits the filter cloth.

  Moreover, although the example which uses the drum-type thing which uses a drum and a belt as an electroosmotic dehydrator was shown in the said embodiment, you may use a flat bed type electroosmotic dehydrator instead. The flat bed type electroosmotic dehydrator places a sludge layer on the flat part of the conveyor belt, pushes down the flat anode and performs electroosmotic dehydration, and with the anode raised, the conveyor belt is the length of the anode plate. Is moved by the amount of. In that case, the sheet forming means may be a conveyor belt and a stamper on a flat plate descending from above.

DESCRIPTION OF SYMBOLS 10 Sludge dewatering apparatus 11, 11a, 11b Sludge 20 Sludge conveyance system 21 Hopper 22 Pump (pressure application means)
23 Kneading machine 24 Water adding device 25 Pressure gauge 26 Transport piping 30 Sludge supply machine 31 Nozzle (sludge supply port)
32 Header pipe 33 Discharge amount adjustment valve 34 Lid 35 Piping 40 Electroosmotic dehydrator 41 Press roll 42 Rotating drum 43 Endless belt 44 Endless filter 45 Roller 46 Dehydrating part 47 Sludge receiving part 50 Supply experiment apparatus 51 Nozzle 52 Header pipe 61a, 61b Pressing roll 62 Drum 69 Sludge spill prevention roll 71 Forming roll

Claims (8)

A system for supplying slurry to a dehydrating part of an electroosmotic dehydrator,
Pressure applying means for applying pressure to the slurry;
A plurality of slurry supply ports located downstream of the pressure application means and spaced apart in the width direction;
Sheet forming means located downstream of the plurality of slurry supply ports and capable of sandwiching the entire width direction of the streaks of slurry discharged from the plurality of slurry supply ports;
A slurry supply system. The sheet forming means includes
It is located upstream of the dehydrating part of the electroosmotic dehydrator,
A belt wrapped around multiple rollers;
The slurry supply system according to claim 1, further comprising a pressing roll disposed at a distance above the belt. The slurry supply system according to claim 1, wherein the pressure applying unit is a pump that pumps the slurry. The slurry supply system according to any one of claims 1 to 3, wherein the slurry supply port is a cylindrical nozzle. The slurry supply system according to claim 4, wherein each of the slurry supply ports includes a valve for adjusting a discharge amount. The slurry is sludge generated from a wastewater treatment facility,
The slurry supply system according to any one of claims 1 to 5. A step of applying pressure to the slurry, and a step of discharging the slurry to which the pressure is applied in a line shape from a plurality of supply ports provided at intervals in the width direction;
A step of sandwiching the entire slurry in the width direction of the plurality of slurries discharged in a line shape and stretching it into a sheet shape;
Supplying the sheet-like slurry to a dehydrating part of an electroosmotic dehydrator. A dehydrating apparatus having a slurry feeder and an electroosmotic dehydrator,
The slurry feeder is
A plurality of slurry supply ports provided at intervals in the width direction for discharging the slurry to which pressure is applied,
The electroosmotic dehydrator is
A rotating drum on the anode side,
A cathode belt wound around a plurality of rollers;
A dewatering section where the drum and the belt face each other;
A receiving part for discharging slurry from the slurry supply port on the belt upstream of the dehydrating part;
Between the receiving part and the dehydrating part, the belt and a thickness adjusting part including a pressing roll provided above the belt via a gap,
Dehydration device.

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