JP2014111242A - Solid-liquid separator and pressure roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid-liquid separator which can smoothly and submissively rotate a pressure roller by using a belt, and can smoothly transport and dehydrate polluted mud, and to provide the pressure roller.SOLUTION: A solid-liquid separator 12 comprises: a filter cloth belt 16 which travels by using driving force from a driving source 17 and transports polluted mud; and a pressure roller 26 which is arranged so as to face a top face 16a of the filter cloth belt 16. The pressure roller 26 comprises: a rotary shaft 60 which is provided so as to freely rotate around a shaft center that is set in a direction orthogonal to a direction in which the polluted mud is transported by the filter cloth belt 16; and an elastic member 66 which is arranged at an outer peripheral side of the rotary shaft 60 and elastically supports an outer peripheral surface of the pressure roller 26.

Description

  The present invention relates to a pressure roller that pressurizes and dewaters sludge between the belt and an upper surface of the belt, and a solid-liquid separation device including the pressure roller.

  Conventionally, a solid-liquid separation device is known in which a pressure roller is pressed onto a filter cloth belt, and sludge such as sewage or factory wastewater is introduced between the filter cloth belt and the pressure roller to perform pressure dehydration. . For example, Patent Document 1 describes a solid-liquid separation device that depressurizes and dewaters sludge between a pressure roller and an endless belt.

Japanese Patent Laid-Open No. 9-75619

  In the apparatus described in Patent Document 1, since the pressure roller does not have a drive source, the configuration is simple and energy saving is achieved. However, depending on the properties of the sludge, the pressure roller slides on the belt and runs idle, so that sufficient dehydration cannot be performed, and sludge may stay in front of the pressure roller. In addition, since the belt is formed of a flexible material, when the belt is bent due to the sludge weight, the gap between the pressure roller and the belt fluctuates, and the sludge concentration (water content) is increased. Variations can also occur.

  A configuration is also conceivable in which the pressure roller is directly rotated by an individual drive source or the like. However, the cost of the drive source is required, and the equipment is increased in size and complexity.

  The present invention has been made in consideration of the above-mentioned conventional problems, and can be used to smoothly rotate a pressure roller with a simple configuration, and to smoothly convey and dewater sludge, An object is to provide a pressure roller.

  The solid-liquid separation device according to the present invention includes a belt that travels by a driving force from a driving source and conveys sludge, and a sludge that is disposed opposite to the upper surface of the belt and that conveys the upper surface between the upper surface and the belt. A solid-liquid separation device that dehydrates sludge and separates it into solid and liquid, and the pressure roller is freely rotatable about a direction orthogonal to the sludge transport direction by the belt as an axis center. A rotating shaft provided; and an elastic member that is disposed on an outer peripheral side of the rotating shaft and elastically supports an outer peripheral surface of the pressure roller, and in a state where no sludge is placed on the upper surface of the belt, It is characterized in that at least a part of the outer peripheral surface is installed at a position in contact with the upper surface of the belt.

  The pressure roller according to the present invention is disposed opposite to the upper surface of the belt that conveys the sludge by running with the driving force from the driving source, and pressurizes the sludge conveyed on the upper surface between the upper surface. A pressure roller that dehydrates by this, characterized in that it has a rotary shaft and an elastic member that is disposed on the outer peripheral side of the rotary shaft and elastically supports the outer peripheral surface of the pressure roller.

  According to such a configuration, when the sludge is pressurized and dehydrated, the elastic member is elastically deformed to accept the sludge. Therefore, even when the sludge is pressurized, at least the outer peripheral surface of the pressure roller The contact state with some belts is maintained, and the belt is always driven stably by the belt regardless of the presence or absence of sludge. This prevents the pressure roller from slipping and slipping on the belt due to the sludge sandwiched between the belt and the sludge smoothly even if the pressure roller is not provided with a separate drive source. Can be transported and dehydrated.

  According to the present invention, since the elastic member is provided on the pressure roller, sludge can be smoothly conveyed and dehydrated without providing an individual drive source for the pressure roller.

FIG. 1 is a side view showing an overall configuration of a sludge dewatering system including a solid-liquid separator according to an embodiment of the present invention. FIG. 2 is a plan view of the solid-liquid separator shown in FIG. FIG. 3 is an explanatory diagram enlarging the periphery of the moving mechanism of the solid-liquid separator shown in FIG. FIG. 4 is a configuration diagram of a pressure roller according to an embodiment of the present invention, FIG. 4 (A) is a partially sectional front view, and FIG. 4 (B) is a side view. FIG. 5 is a front sectional view showing a state in which sludge is crushed by the pressure roller shown in FIG. 4. 6 is a configuration diagram of a pressure roller according to a first modification, FIG. 6 (A) is a partially sectional front view, and FIG. 6 (B) is a side view. FIG. 7 is a front sectional view showing a state in which sludge is crushed by the pressure roller shown in FIG. FIG. 8 is a front sectional view of a pressure roller according to a second modification. FIG. 9 is a configuration diagram of a pressure roller according to a third modification, FIG. 9 (A) is a partially sectional front view, and FIG. 9 (B) is a side view. FIG. 10 is a configuration diagram of a pressurizing unit according to a modification, FIG. 10 (A) is a partially sectional front view, and FIG. 10 (B) is a side view. FIG. 11 is a front sectional view showing a state in which sludge is crushed by the pressurizing unit shown in FIG. 10. FIG. 12 is a front sectional view showing an example of a state in which sludge is crushed by the pressurizing unit shown in FIG. 4. FIG. 13 is a side view showing the configuration of the solid-liquid separation device according to the first modification. FIG. 14 is a plan view of the solid-liquid separator shown in FIG. FIG. 15 is a side view showing the configuration of the solid-liquid separator according to the second modification. 16 is a plan view of the solid-liquid separator shown in FIG. FIG. 17 is a side view showing the configuration of the solid-liquid separator according to the third modification. FIG. 18 is a plan view of the solid-liquid separator shown in FIG. FIG. 19 is an explanatory side view showing the configuration of the solid-liquid separation device according to the fourth modification. FIG. 20 is an explanatory side view showing the configuration of the solid-liquid separation device according to the fifth modification.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a solid-liquid separation apparatus including a pressure roller according to the present invention will be described in detail with reference to the accompanying drawings by giving preferred embodiments in relation to a sludge dewatering system to which the apparatus is applied.

1. Description of Overall Configuration of Sludge Dewatering System FIG. 1 is a side view showing the overall configuration of a sludge dewatering system 10 including a solid-liquid separation device 12 according to an embodiment of the present invention, and FIG. 2 is shown in FIG. 3 is a plan view of the solid-liquid separator 12. FIG. The sludge dewatering system 10 shown in FIG. 1 is obtained by concentrating sludge (for example, sewage sludge) by gravity filtration with an upper solid-liquid separator (concentrator) 12 and then dehydrating under pressure with a lower dewaterer 14. This is a sludge treatment facility that discharges as dehydrated cake. The solid-liquid separator 12 can be applied to systems other than the system combined with the dehydrator 14 as described above, and the solid-liquid separator 12 may be used alone.

  The sludge dewatering system 10 includes a solid-liquid separation device 12 including a filtration unit 18 that gravity filters (gravity concentration) sludge on an upper surface 16a of a filter cloth belt (filter body, belt) 16 that travels in an endless track, and a solid-liquid separation. A dewatering device 14 that conveys the sludge that has been solid-liquid separated and concentrated by the device 12 while being sandwiched between the pair of filter cloth belts 20 and 22 and dehydrates under pressure is provided. Immediately before the solid-liquid separator 12, a coagulation mixing tank 24 is provided for mixing the polymer coagulant (first drug) F1 into the sludge transported from the preceding equipment of the sludge dewatering system 10. . As the polymer flocculant F1, generally known ones may be used, and examples thereof include an anionic polymer flocculant and a cationic polymer flocculant.

1.1 Description of Solid-Liquid Separator First, the solid-liquid separator 12 will be described.

  As shown in FIGS. 1 and 2, the solid-liquid separation device 12 according to the present embodiment includes a filtration unit 18 that gravity-filters sludge that has been input from the coagulation mixing tank 24 to the upper surface 16 a of the filter cloth belt 16, and a filtration unit And a pressure unit 28 that depressurizes and dewaters the sludge that has been gravity filtered in 18 by a pressure roller (dehydration roller) 26 and discharges the sludge to the lower dewatering device 14. A moving mechanism 30 that moves sludge in a direction that intersects (orthogonally in FIG. 2) the conveying direction by the filter cloth belt 16 is provided in the middle of the filtering unit 18.

  The filtration unit 18 is composed of an upper surface (outer peripheral surface) 16a of an endless filter cloth belt 16 that is wound around a plurality of rollers 19a, 19b, 19c, 19d, and 19e and driven to rotate in one direction. The sludge is placed on the upper surface 16a of the filter cloth belt 16 stretched between 19e, so that water contained in the sludge is filtered and separated by gravity.

  The filter cloth belt 16 is constituted by, for example, a long band-shaped filter cloth having water permeability, a long band-shaped metal screen in which a plurality of fine holes are formed in a mesh shape, and the like. The filter cloth belt 16 is wound around each of the rollers 19a to 19e with sufficient tension, and the direction of the arrow shown in FIG. 1 by the driving force from the driving source (rotary driving source) 17 composed of a motor or the like. It can travel in the counterclockwise direction in FIG. 1 and 2, the direction from the right side (upstream side) to the left side (downstream side) is the sludge transport direction in the solid-liquid separator 12. For example, the drive source 17 is illustrated by winding a drive belt 17b (for example, a belt or a chain) between the rotation shaft 17a and the rotation shaft 23 of a predetermined drive roller (roller 19a in this embodiment). The filter cloth belt 16 is made to travel at a desired speed via a speed reduction mechanism that does not.

  Therefore, the sludge thrown in and placed from the outlet port 24a of the flocculation / mixing tank 24 at the upstream position of the filtration unit 18 is transported downstream by the filter cloth belt 16, while only the moisture passes through the filter cloth belt 16 by gravity. Permeated, filtered and dehydrated, the filtered water (separated liquid, filtrate) is collected by the filtrate receiving trays 32a and 32b (see FIG. 1).

  On the upper surface 16a of the filter cloth belt 16 constituting the filtration unit 18, a plurality of rod bodies (ploughs) 34 (in FIG. 2, a total of 12 configurations are illustrated before and after the moving mechanism 30) are provided upright. . The rod body 34 is an obstacle for promoting the draining of water by bringing the bar 34 into contact with the sludge transported on the filter cloth belt 16 and dispersing or gathering them by appropriately setting the arrangement thereof. The number, shape, etc. can be changed as appropriate. Note that a part of the rod body 34 installed on the upstream side of the screws 40a and 40b may be replaced with a hard roller (not shown) to be used for general dehydration. In that case, it is preferable to provide a slight gap between the roller and the filter cloth belt 16, so that the roller is used not for dehydration but for simple draining. There may be a plurality of the rollers.

  A second chemical injection device (chemical injection device, chemical addition device) for adding an iron-based inorganic flocculant (second chemical) F2 to the sludge to be conveyed on the upstream side of the moving mechanism 30 in the filtration unit 18. 36 is provided. The second chemical injection device 36 includes a chemical tank 36a for storing the inorganic flocculant F2, and a first line 36c and a second line 36d branched from the outlet of the chemical tank 36a by a two-way valve 36b. As the inorganic flocculant F2, generally known ones may be used, and examples thereof include iron-based and aluminum-based ones.

  As shown in FIG. 2, in the present embodiment, the first line 36 a is further branched into two in parallel, and the two first lines 36 c and 36 c are arranged in the width direction of the filter cloth belt 16 at the upstream position of the moving mechanism 30. The addition nozzles 36e are provided in the vicinity of both side portions of the filter cloth belt 16, respectively. Of course, the first line 36a may be used as it is without branching. As indicated by a broken line in FIG. 1, the second line 36d is arranged so that the inorganic flocculant F2 can be added to the sludge charged into the flocculation mixing tank 24. Although not shown, the second line 36d The configuration may be the same as that of the addition nozzle 36e. In the normal operation state of the present embodiment, the two-way valve 36b is controlled to be switched to the first line 36c side under the control of a control device (not shown).

  On the other hand, the above-described polymer flocculant F1 is added to the sludge immediately before being put into the agglomeration mixing tank 24 by the first chemical injection device (drug addition device) 38 in the normal operation state of the present embodiment. The first chemical injection device 38 includes a chemical tank 38a for storing the polymer flocculant F1, and a first line 38c and a second line 38d branched from the outlet of the chemical tank 38a by a two-way valve 38b.

  As shown in FIG. 1, the first line 38c can add the polymer flocculant F1 to the sludge charged into the flocculation mixing tank 24 at a position downstream of the second line 36d of the second chemical injection device 36. It is arranged. As shown by a broken line in FIG. 2, the second line 38 d extends across the width direction of the filter cloth belt 16 at the upstream position of the first line 36 d of the second chemical injection device 36, and both sides of the filter cloth belt 16. An addition nozzle 38e is provided in the vicinity of each portion. In the normal operating state of the present embodiment, the two-way valve 38b is controlled to be switched to the first line 38c side under the control of a control device (not shown).

  During normal operation, the coagulation mixing tank 24 into which the sludge to which the polymer flocculant F1 is added from the first chemical injection device 38 is introduced has a tank 24b in which the sludge is stored, and the sludge in the tank 24b to the motor 24c. And a stirring blade 24d for stirring. The sludge in which the polymer flocculant F1 is sufficiently mixed in the tank 24b by the stirring blade 24d is put into the upper surface 16a of the filter cloth belt 16 from the outlet port 24a.

  Next, the moving mechanism 30 provided in the middle of the filtering unit 18 moves the sludge conveyed on the filter cloth belt 16 in the crossing direction, while reducing the width direction size and simultaneously increasing the sludge height. By doing so, the inorganic flocculant F2 added by the second chemical injection device 36 is sufficiently kneaded. Thereby, the filtration efficiency of the sludge in the solid-liquid separator 12 and the dehydrator 14 can be improved, and the sludge concentration can be increased.

  The moving mechanism (screw conveyor) 30 opens toward the entire upstream surface of the upper surface 16a of the filter cloth belt 16 so as to accept the sludge, and moves the sludge in a direction perpendicular to the conveying direction by the filter cloth belt 16. And a pair of guide plates 42a and 42b that are disposed close to the downstream side of the screws 40a and 40b and are erected on both ends in the width direction of the filter cloth belt 16, respectively. In the moving mechanism 30, a gap between the guide plates 42 a and 42 b (substantially the same as the gap between the screws 40 a and 40 b) and a passage (sludge passage 43) for discharging sludge downstream from the moving mechanism 30. It has become.

  The screws 40a and 40b extend in a direction orthogonal to the sludge transport direction by the filter cloth belt 16 and extend across the filter cloth belt 16 in the width direction, and outer peripheral surfaces on both sides except for the vicinity of the center of the screw shaft 44. And screw blades 41a and 41b provided in a spiral shape.

  Both ends of the screw shaft 44 are pivotally supported at positions outside the filter cloth belt 16 in the width direction by a bearing (not shown). For example, a flexible power such as a chain or a belt is applied to the roller 19a around which the filter cloth belt 16 is wound. By being linked by the transmission member 39 (see the two-dot chain line in FIG. 1), it can be rotated as the filter cloth belt 16 travels. When the traveling operation of the filter cloth belt 16 and the rotation operation of the screw shaft 44 are synchronized, the diameter of each shaft around which the flexible power transmission member 39 is wound is appropriately designed, or a reduction device (not shown) is mounted. Thus, the relationship between the sludge conveyance speed by the filter cloth belt 16 and the rotation speed of the screw shaft 44 (that is, the sludge movement speed by the screws 40a and 40b) can be easily set and controlled. Of course, a drive source such as a motor that independently rotates the screw shaft 44 may be provided.

  The screw blades 41a and 41b constituting the screws 40a and 40b are respectively provided on the outer peripheral surface of the screw shaft 44 at positions close to both sides in the width direction of the filter cloth belt 16, and the tip ends of the screw blades 41a and 41b are guide plates 42a and 42b. It faces through a gap of the same degree as the gap between them. The direction of the spiral of each screw blade 41a, 41b is a contrast shape (reverse direction) at the center line of the filter cloth belt 16, and the direction of sludge movement by each screw 40a, 40b is set in the opposite direction. Yes. For this reason, each screw 40a, 40b moves sludge from the outer side toward the inner side (center) in the width direction of the filter cloth belt 16, and at the center part where the tips are separated from each other via the gap, both outer sides The sludge moved from each other is pressed against each other and consolidated, and the inorganic flocculant F2 is sufficiently kneaded in the sludge (see also FIG. 3). Each screw 40a, 40b is good also as a structure using each screw shaft instead of the structure using the common screw shaft 44. FIG.

  In the case of the present embodiment, the sludge that has been conveyed on the center side in the width direction of the filter cloth belt 16 to the central portion of the screw shaft 44, that is, the outer peripheral surface of the screw shaft 44 exposed between the screws 40a and 40b, and a pair of A plurality of paddles 45 for smoothly discharging the sludge consolidated in the center by the screws 40a, 40b to the downstream side are provided. The paddle 45 is, for example, an impeller provided in pairs on the outer peripheral surface of the screw shaft 44 along the circumferential direction.

  The guide plates 42a and 42b are provided on the downstream side of the screws 40a and 40b and at a position close to the screws 40a and 40b. It has a bottom portion 47 that covers the lower half of the screws 40a and 40b by curving and projecting toward the upstream side. A pair of passage plates 48a and 48b extending downstream along the sludge transport direction by the filter cloth belt 16 are provided at the center ends of the guide plates 42a and 42b, respectively. The gap between the guide plates 42a and 42b is located on the front side in the direction of sludge movement by the screws 40a and 40b, and this gap forms a sludge passage 43 for discharging the sludge downstream. Yes.

  The wall portion 46 is a plate-like member set to a height approximately equal to the height of the screws 40a and 40b, and the height can be changed as appropriate. As shown in FIG. 1, the bottom portion 47 is a plate-like member that protrudes from the lower end of the wall portion 46 toward the upstream side in the transport direction to a position that is approximately the center of the screws 40 a and 40 b, and has a length. Can be appropriately changed. For the wall portion 46 and the bottom portion 47 constituting the guide plates 42a and 42b, a screen or the like in which many fine holes are formed may be used.

  The passage plates 48a and 48b are erected so as to face each other with a gap having the same width as the gap formed between the screw blades 41a and 41b and between the guide plates 42a and 42b. The passage plates 48a and 48b are wall members that form a passage for smoothly discharging sludge, which is compacted near the center of the filter cloth belt 16 by the screws 40a and 40b, to the downstream side. Set to a height of about. In practice, the sludge consolidated in the center by the screws 40a and 40b is moved downstream from the sludge passage 43 formed between the pair of guide plates 42a and 42b (wall portion 46) by the traveling of the filter cloth belt 16. The passage plates 48a and 48b can be omitted. However, if the passage plates 48a and 48b are provided, the sludge that has been consolidated in the center and increased in height can be more smoothly conveyed to the downstream side. Can do.

  Next, the pressurizing unit 28 constitutes a front dewatering unit (primary dewatering unit) of the dewatering device 14 disposed below the solid-liquid separation device 12, and the outer peripheral surface of the filter cloth belt 16. Is provided with a pressure roller 26 arranged in pressure contact.

  The sludge that has been filtered and concentrated by the filtration unit 18 and has been sufficiently kneaded with the inorganic flocculant F2 by the moving mechanism 30 and has been increased in thickness by the compaction is between the pressure roller 26 and the filter cloth belt 16 in the pressure unit 28. After dehydrating under pressure, it is discharged / dropped from the outlet of the pressurizing unit 28 (exit of the solid-liquid separation device 12) and put into the dehydrator 14 in the next step. The pressurizing unit 28 crushes the sludge that has been consolidated by the moving mechanism 30 and gathered in the center, and sends it to the dehydrating device 14 in a state where it is spread again in the width direction of the filter cloth belt 16, and put into the dehydrating device 14. It also has a function of increasing the dewatering area of the sludge and improving the dewatering efficiency here.

  FIG. 4 is a configuration diagram of the pressure roller 26 according to an embodiment of the present invention, FIG. 4 (A) is a partially sectional front view, and FIG. 4 (B) is a side view.

  As shown in FIG. 2, FIG. 4 (A) and FIG. 4 (B), the pressure roller 26 has a rotating shaft 60 made of a hard member such as metal or resin at the center thereof. For example, the left and right ends of the rotating shaft 60 are pivotally supported by bearing brackets 62 and 62, respectively. The rotating shaft 60 is freely installed around a direction perpendicular to the sludge conveyance direction by the filter cloth belt 16. A pair of left and right hard members 64, 64 in which a metal, a resin, or the like is formed in a cylindrical shape is provided on both ends of the outer peripheral surface of the rotating shaft 60. Sponges, rubber, etc. are provided between the hard members 62, 62 on both ends. An elastic member (elastic body) 66 having a cylindrical shape is provided.

  A filter cloth 68, which is a flexible sheet-like member, is wound around the outer peripheral surface formed by the left and right hard members 64 and the central elastic member 66, and the filter cloth 68 is wound around the outer periphery of the pressure roller 26. The surface is formed. The filter cloth 68 is made of the same material as the filter cloth belt 16, for example. In the filter cloth 68, the inner surfaces of both ends in the axial direction of the rotary shaft 60 are firmly supported by the hard member 64, while the inner surface of the central portion between them is elastically supported by the elastic member 66. By this elastic member 66, the pressure roller 26 is configured as an elastic roller having an outer peripheral surface having elasticity.

  As shown in FIG. 4A, the pressure roller 26 has at least a part in the axial direction of the outer peripheral surface (the outer surface of the filter cloth 68) in a state where no sludge is placed on the upper surface 16a of the filter cloth belt 16. 4 (all in the axial direction in FIG. 4) is installed at a position in contact with the upper surface 16 a of the filter cloth belt 16, and is driven to rotate as the filter cloth belt 16 runs.

  Returning to FIG. 1, an inclined plate 49 is disposed between the pressurizing unit 28 and the lower dewatering device 14. The inclined plate 49 is a guide for smoothly guiding the sludge discharged / dropped from the solid-liquid separator 12 onto the filter cloth belt 22 that is the input position of the dehydrator 14.

1.2 Description of Dehydration Device Next, the dehydration device 14 will be described.

  As shown in FIG. 1, the dehydrating device 14 is a dehydrating unit that depressurizes and dewaters sludge introduced from the outlet of the solid-liquid separator 12 via the inclined plate 49 while being transported between the pair of filter cloth belts 20 and 22. 50 and a squeezing part 52 that further pressurizes and squeezes the sludge dehydrated by the dehydrating part 50, and has substantially the same configuration as a general belt press type dehydrator.

  The lower filter cloth belt 20 is configured by, for example, a long band-shaped filter cloth having water permeability, a long band-shaped metal screen in which a plurality of fine holes are formed in a mesh shape, and the like. The filter cloth belt 20 is wound between a plurality of rollers 21a, 21b, 21c, 21d, 21e, 21f, 21g, 21h, 21i, 21j, 21k, 21l, 21m, 21n with sufficient tension, not shown. A drive source such as a motor can travel in the direction of the arrow shown in FIG. 1 (clockwise in FIG. 1).

  In a similar manner, the upper filter cloth belt 22 is constituted by, for example, a long belt-like filter cloth having water permeability, a long belt-like metal screen in which a plurality of fine holes are formed in a mesh shape, and the like. The The filter cloth belt 22 is wound between a plurality of rollers 21o, 21b, 21c, 21d, 21e, 21f, 21g, 21h, 21i, 21j, 21p, and 21q with sufficient tension, and is driven by a motor or the like (not shown). The vehicle can travel in the direction of the arrow shown in FIG. 1 (counterclockwise in FIG. 1).

  A portion where the outer peripheral surfaces (surfaces) of the lower filter cloth belt 20 and the upper filter cloth belt 22 between the rollers 21b to 21i are in contact (or close) while meandering up and down constitutes the dewatering unit 50. During this time, the sludge is sufficiently pressurized and dehydrated. Moreover, the part which contact | abutted (or adjoined) the outer peripheral surface (surface) of the lower filter cloth belt 20 and the upper filter cloth belt 22 between the rollers 21j and 21p comprises the pressing part 52. The sludge is further pressurized and pressed between the rollers 21j and 21p serving as pressing rollers, and is discharged to the outside as a dehydrated cake having a desired moisture content.

  In the vicinity of the inlet of the dehydrator 14, the height of sludge dropped and introduced from the outlet of the solid-liquid separator 12 onto the filter cloth belt 20 is made uniform to some extent, and is formed between the filter cloth belts 20 and 22. A leveling plate 51 is provided for smooth introduction into the inlet 50a of the dewatering unit 50. The leveling plate 51 is a plate member that is disposed slightly above the downstream side of the sludge falling position from the solid-liquid separator 12 onto the filter cloth belt 20, and is gradually inclined downward toward the inlet 50a. You may form with the leaf | plate spring member urged | biased in the direction pressed against.

  At the outlet of the dewatering device 14, a discharge tray 54 is installed in an inclined posture with the rear end lowered so as to be close to the filter cloth belt 20 running on the outer peripheral surface of the roller 21 j. The dehydrated cake is discharged while sliding on the discharge tray 54. Above the discharge tray 54, a scraper (scraping plate) 56 is installed in an inclined posture with the rear end raised so as to be close to the filter cloth belt 22 running on the outer peripheral surface of the roller 21p. The sludge that is not discharged to the discharge tray 54 from between the rollers 21j and 21p but remains attached to the upper filter cloth belt 22 is scraped off by the scriber 56 and discharged to the discharge tray 54. The sludge that remains attached to the lower filter cloth belt 20 is scraped off by the discharge tray 54 and slides down on the discharge tray 54 as it is.

  In such a dewatering device 14, the sludge introduced onto the filter cloth belt 20 from the solid-liquid separator 12 is drawn between the filter cloth belts 20 and 22 constituting the dewatering unit 50 from the inlet 50 a and is sandwiched and pressurized. In this state, it is conveyed downstream. During this time, only moisture passes through the filter cloth belt 20 by the pressure applied by the two filter cloth belts 20 and 22, and is filtered and dehydrated. Further, after being squeezed by the squeezing unit 52, it is discharged onto the discharge tray 54 as a dehydrated cake. The water filtered by the dewatering unit 50 and the pressing unit 52 passes through the filter cloth belt 20 and falls, and is collected by the filtrate receiving tray 58.

  As shown in FIG. 1, in the sludge dewatering system 10 according to the present embodiment, unlike the system generally used conventionally, the filter cloth belt 16 of the solid-liquid separator 12 and the filter cloth belt 20 of the dewaterer 14 are used. , 22 are not used together, and each of them is configured to travel on an independent endless track. For this reason, it is possible to easily control the traveling speed of the filter cloth belt 16 of the front-stage solid-liquid separator 12 and the traveling speed of the filter cloth belts 20 and 22 of the rear-stage dewatering apparatus 14 to different speeds. In this case, it is preferable to set and control the traveling speeds of the filter cloth belts 20 and 22 of the dehydrator 14 to be slower than the traveling speed of the filter cloth belt 16 of the solid-liquid separator 12. That is, in the sludge dewatering system 10, since the moving mechanism 30 is mounted on the solid-liquid separation device 12, the dewatering rate is greatly increased as compared with the conventional concentrating device. The amount of sludge to be produced (the amount of cake) can be greatly reduced, and even if the traveling speed of the filter cloth belts 20 and 22 in the dewatering device 14 is slowed, the total amount of sludge to be charged can be sufficiently dehydrated. It is possible. Then, by slowing the traveling speed of the filter cloth belts 20 and 22 in the dehydrator 14, the time required to pass between the filter cloth belts 20 and 22 during the dehydration can be lengthened, and the dehydrator 14 has a compact configuration. However, high dewatering performance can be obtained.

2. Next, the operation and effect of the sludge dewatering system 10 will be described.

  First, the sludge that is the object to be concentrated and dewatered by the sludge dewatering system 10 is added to the flocculation mixing tank 24 with the predetermined polymer flocculant F1 added by the first line 38c of the first chemical injection device 38. be introduced. The sludge introduced into the tank 24b of the agglomeration mixing tank 24 is sufficiently stirred and mixed by the stirring blade 24d to form a floc, and from the outlet port 24a to the upstream side of the upper surface 16a of the filter cloth belt 16, that is, the solid-liquid separator 12. To the entrance.

  The sludge thrown into the solid-liquid separator 12 is transported through the filter unit 18 by the traveling filter cloth belt 16 and is gravity filtered (gravity dehydration) while receiving a draining promoting action by the rod body 34 on the way. During this time, as shown in FIGS. 2 and 3, a predetermined inorganic flocculant F2 is dripped from the addition nozzle 36e of the second chemical injection device 36 to the sludge conveyed on both sides in the width direction of the filter cloth belt 16. Meanwhile, the sludge reaches the moving mechanism 30.

  As shown in FIG. 3, in the moving mechanism 30, the sludge that is transported on both sides in the width direction of the filter cloth belt 16 and added with the inorganic flocculant F <b> 2 in a continuous belt shape in the transport direction is supplied to each screw 40 a, 40 b. When it is caught in the rotation, it moves while being pushed toward the center while being guided by the guide plates 42a and 42b. At this time, the inorganic flocculant F2 is attached to each lump of small sludge that is moved while being cut at regular intervals by the rotating screw blades 41a and 41b.

  The sludge moved by the screws 40a and 40b with the inorganic flocculant F2 is mixed with the sludge that has been transported through the central portion (center portion) of the filter cloth belt 16. At the same time, sludges are crushed and consolidated in the center of the filter cloth belt 16 by the pressing force of the screws 40a and 40b. As a result, the sludge is passed through the sludge passage 43 from the passage plates 48a and 48b to the downstream side while the rotational force of the paddle 45 is applied while the width direction dimension is reduced and the height (bulk) is increased. During this time, gravity filtration by the filter cloth belt 16 is continued and concentrated to a desired concentration. In addition, since the filter cloth belt 16 is running at the front and rear positions of the screws 40a and 40b, even if the paddle 45 is omitted, the sludge compacted by the screws 40a and 40b is used as the opening between the guide plates 42a and 42b. Of course, it is possible to discharge smoothly from the sludge passage 43 to the downstream side.

  In such a concentration process by the solid-liquid separator 12, for example, as shown in FIGS. 1 and 2, the filter cloth belt 16 extends to the width W 1 in the width direction of the filter cloth belt 16 and enters at a height h 1. When the sludge is discharged from the moving mechanism 30, the sludge is reduced to a width W2 that is narrower than the width W1, so the height direction dimension increases to a height h2 by the reduction in the surface area in plan view, It is in a fully consolidated state. For this reason, the concentration concentration of sludge increases significantly compared with the case where it receives only normal gravity filtration with a general concentration apparatus. Further, since the sludge height is increased on the downstream side from the moving mechanism 30, the gravity filtration efficiency is further improved by its own weight, and the inorganic flocculant F2 is sufficiently kneaded by the screws 40a and 40b. Therefore, even the sludge that has been sufficiently dehydrated and concentrated up to the moving mechanism 30 can further promote concentration by gravity filtration. Further, when the sludge is moved to the central portion by the screws 40a and 40b, the sludge is compressed while being moved by the rotational force of the guide plates 42a and 42b and the screw blades 41a and 41b, so that the concentration of the sludge is further increased. It will be. At this time, the moisture of the sludge compressed by the screws 40 a and 40 b flows from the wall portion 46 through the bottom portion 47 and is filtered by the filter cloth belt 16.

  The sludge consolidated by the moving mechanism 30 is transported further downstream and introduced into the pressurizing unit 28 while receiving drainage promoting action by the rod 34 on the downstream side. The sludge introduced into the pressurizing unit 28 is sandwiched and pressed between the pressure roller 26 and the filter cloth belt 16 to spread from the width W2 to the width W3, and is added while the height h3 is lower than the height h2. After being dewatered by pressure, it is discharged and dropped, and it slides on the inclined plate 49 and is put into the dehydrator 14. The sludge once consolidated by the moving mechanism 30 is flattened again by the pressurizing unit 28, whereby the dewatering area of the sludge in the dewatering device 14 which is a subsequent process can be expanded and the dewatering efficiency can be improved.

  In this case, the pressure roller 26 is installed at a position where the outer peripheral surface of the pressure roller 26 is in contact with the upper surface 16a of the filter cloth belt 16 in the longitudinal direction with no sludge placed on the upper surface 16a of the filter cloth belt 16. The filter cloth belt 16 can be driven to rotate by traveling (FIGS. 4A and 4B). As shown in FIG. 5, when the sludge S discharged from the moving mechanism 30 and compacted near the center of the filter cloth belt 16 is caught between the pressure roller 26 and the filter cloth belt 16, it is supported by the hard member 64. While the both ends of the filter cloth 68 are in contact with the filter cloth belt 16, the center part of the filter cloth 68 elastically supported by the elastic member 66 is elastically recessed inward by the sludge S, and the sludge S is flattened. Squeeze and dehydrate under pressure.

  The sludge dropped and introduced to the inlet side of the dewatering device 14 through the pressurizing unit 28 is transported by the traveling filter cloth belt 22 and leveled by the leveling plate 51, and then first from the inlet 50a to the dewatering unit 50. And introduced. In the dewatering unit 50, the sludge is nipped and pressurized between a pair of upper and lower filter cloth belts 20, 22 that meander and is transported while being efficiently dehydrated, and then introduced into the pressing unit 52. In the squeezing section 52, the sludge is sandwiched between the pair of filter cloth belts 20 and 22, and is strongly pressed and squeezed between the rollers 21j and 21p serving as squeezing rollers to form a dehydrated cake having a desired moisture content, and discharged. The paper is discharged from the tray 54 to the outside of the system.

  As described above, the solid-liquid separation device 12 according to the present embodiment is disposed so as to face the filter cloth belt 16 that travels by the driving force from the drive source 17 and conveys sludge, and the upper surface 16a of the filter cloth belt 16. The apparatus includes a pressure roller 26 that pressurizes the sludge conveyed on the upper surface 16a with the upper surface 16a, and dewaters the sludge to separate it into solid and liquid. Here, the pressure roller 26 includes a rotary shaft 60 and an elastic member 66 that is disposed on the outer peripheral side of the rotary shaft 60 and elastically supports the outer peripheral surface of the pressure roller 26. In a state where no sludge is placed on the upper surface 16 a, at least a part of the outer peripheral surface is installed at a position in contact with the upper surface of the filter cloth belt 16.

  When the pressure roller 26 pressurizes and dewaters sludge, the elastic member 66 can be elastically deformed to accept the sludge. Therefore, at least a part of the outer peripheral surface of the pressure roller 26 (in this embodiment, hard members at both ends) The contact state of the portion supported by 64 and its adjacent portion to the filter cloth belt 16 is maintained, and the driven belt 16 is always stably driven by the filter cloth belt 16 regardless of the presence or absence of sludge (see FIGS. 4 and 4). (See FIG. 5).

  Therefore, as in the prior art, the pressure roller 26 is prevented from slipping and slipping on the filter cloth belt 16 by inserting sludge between the filter cloth belt 16 and the pressure roller 26 is individually separated. Even with a simple configuration in which no drive source is provided, sufficient dehydration can be performed, and sludge can be prevented from staying in front of the roller. A separate drive source for the pressure roller 26 may be provided. In this case as well, the gap between the pressure roller 26 and the filter cloth belt 16 is always kept substantially constant, and the sludge is concentrated. Effects such as stabilization of the concentration (water content) can be obtained.

  Furthermore, since the elastic member 66 elastically supporting the outer peripheral surface is elastically deformed by the pressure when the sludge is sandwiched in the pressure roller 26, for example, when the filter cloth belt 16 is bent due to the sludge weight or the like. In addition, the gap between the pressure roller 26 and the filter cloth belt 16 is always kept substantially constant, and the concentrated concentration (water content) of the sludge can be stabilized. Moreover, since the filter cloth belt 16 and the filter cloth 68 forming the outer peripheral surface of the pressure roller 26 are made of the same material, it is possible to prevent damage to each other as much as possible. Note that the filter cloth 68 is not provided, and the outer peripheral surface of the pressure roller 26 is formed by the elastic member 66 and the hard members 64 at both ends thereof, and the outer peripheral surface of the elastic member 66 is substantially directly connected to the pressure roller 26. The outer peripheral surface may be elastically supported, and the same applies to the pressure rollers 26a to 26c described below. That is, even when there is no filter cloth 68, the filter cloth belt 16 and the pressure roller 26 rotate at the same speed, so that the pressure roller 26 on the filter cloth belt 16 is always fixed. The filter cloth belt 16 is not damaged by friction or the like.

  As shown in FIGS. 4 and 5, the pressure roller 26 has a hard member 64 provided at both ends of the rotating shaft 60, and an elastic member 66 is provided between the hard members 64 at both ends. It has become. For this reason, the outer peripheral surface supported by the elastic member 66 at the center portion is elastically recessed by sludge entrained between the pressure roller 26 and the filter cloth belt 16, while the outer periphery supported by the hard members 64 on both sides thereof. Since the surface stably maintains the contact state with the filter cloth belt 16, it is possible to more reliably prevent idling of the pressure roller 26 due to the sludge being caught.

  In the solid-liquid separator 12, a screw 40a that extends upstream of the pressure roller 26 in a direction that intersects the conveying direction of the sludge by the belt and moves the sludge in a direction that intersects the conveying direction by the belt by rotation thereof. 40b. For this reason, it can compact by moving sludge with screws 40a and 40b, and can raise the concentration concentration further. Further, the sludge collected in the center by the screws 40a, 40b is flattened by the pressurization unit 28 provided with the pressure roller 26, thereby expanding the dewatering area of the sludge in the dewatering device 14 which is a subsequent process, The dehydration efficiency can be improved.

  At this time, in the solid-liquid separator 12, the sludge by the screw 40 a (40 b) is positioned downstream of the screw 40 a (40 b) in the sludge conveyance direction by the filter cloth belt 16 and close to the screw 40 a (40 b). The guide plates 42a and 42b that guide the movement of are raised. Accordingly, the sludge can be moved by the screws 40a and 40b while being dammed by the guide plates 42a and 42b, so that the sludge can be kneaded more uniformly, and further, the concentrated concentration can be further increased by pressing the sludge. be able to.

  The sludge dewatering system 10 including such a solid-liquid separator 12 includes a dehydrator 14 that depressurizes and dehydrates sludge discharged from the solid-liquid separator 12, and the solid-liquid separator 12 includes the first A filtration unit 18 that gravity-filters sludge to which a drug (for example, polymer flocculant F1) has been added, and a second drug (for example, inorganic flocculant F2) that is added to the sludge transported through the filter unit 18 A chemical injection device 36 and a moving mechanism 30 that moves the sludge to which the second chemical is added in a direction intersecting the conveying direction by the filter cloth belt 16 are provided.

  Therefore, in the sludge dewatering system 10, the first chemical is added in the solid-liquid separator 12, and the second chemical is added to the sludge concentrated to some extent by gravity filtration in the filtration unit 18, and then the moving mechanism. By moving the sludge in the direction crossing the conveying direction of the filter cloth belt 16 at 30, the sludge can be sufficiently kneaded with the second chemical during this movement and further consolidated, and the sludge in the solid-liquid separator 12 can be further consolidated. The concentration / dehydration rate can be improved, and the concentration can be increased. Furthermore, after adding and concentrating the first chemical, the second chemical injection device 36 for adding the second chemical, the moving device 30 for kneading the second chemical, and the elastic roller for pressure-dehydrating sludge And the pressure roller 28 provided with the pressure roller 26 are provided in the solid-liquid separation device 12, and the dehydration device 14 for pressure-dehydrating sludge is provided at the subsequent stage, whereby the polymer flocculant F1 and the inorganic flocculant While reducing the amount of F2 used, it is possible to greatly reduce the moisture content of the sludge with a compact configuration and further increase the concentration concentration of the sludge.

3. 3. Description of Modification Example of Pressure Roller 3.1 Description of Pressure Roller According to First Modification Example The above-described pressure roller 26 has a hard member 64 disposed at both ends thereof so that the contact state with the filter cloth belt 16 is further improved. Although it has a structure that can be reliably maintained, as shown in FIGS. 6 (A) and 6 (B), a hard member (not shown) is interposed directly on the outer peripheral surface of the rotating shaft 60 that is a hard member, You may comprise as the pressure roller 26a of the structure where the cylindrical elastic member 66 was provided.

  Similar to the pressure roller 26 shown in FIG. 4, the pressure roller 26 a has an outer peripheral surface extending in the longitudinal direction on the upper surface 16 a of the filter cloth belt 16, and the upper surface of the filter cloth belt 16. It is installed at a position in contact with 16a and can be driven and rotated by traveling of the filter cloth belt 16 (FIGS. 6A and 6B). Then, as shown in FIG. 7, when the sludge S is caught between the pressure roller 26 a and the filter cloth belt 16, both ends of the filter cloth 68 at a position away from the sludge S are in contact with the filter cloth belt 16. While the state is maintained, the central portion of the filter cloth 68 elastically supported by the elastic member 66 is elastically recessed inward by the sludge S, and the sludge S is flattened and dehydrated under pressure.

  In this way, the pressure roller 26a does not have the hard members 64 disposed at both ends thereof, and can sufficiently perform substantially the same operation as the pressure roller 26 while having a simple structure. In particular, the pressure roller 26 a is provided with a moving mechanism 30 on the upstream side thereof, like the solid-liquid separator 12, and applied to an apparatus having a configuration in which the introduced sludge is always gathered at the center of the filter cloth belt 16. 4 is advantageous over the pressure roller 26 shown in FIG. 4 in terms of cost and the like because a part of the outer peripheral surface can be always kept in stable contact with the filter cloth belt 16. Needless to say, the hard member 64 similar to that of the pressure roller 26 may be provided only at one end of the rotating shaft 60.

3.2 Description of Pressure Roller According to Second Modification As shown in FIG. 8, the pressure roller 26 may be configured as a pressure roller 26b having a structure combined with the pressure roller 26a. Good.

  In the pressure roller 26b, the outer diameters of the hard members 64 and 64 at both ends of the pressure roller 26 shown in FIG. 4 are reduced, and cylindrical elastic members (second elastic members) 65 and 65 are arranged on the outer peripheral surface thereof. It has a configuration. Thereby, in the pressure roller 26b, the whole outer peripheral surface is elastically supported by the elastic members 65 and 66 similarly to the pressure roller 26a shown in FIG. Accordingly, since the entire surface of the pressure roller 26b is elastically contacted with the upper surface 16a of the filter cloth belt 16, the pressure roller 26b is similar to the pressure roller 26a shown in FIG. 6 as compared with the pressure roller 26 shown in FIG. Further, the contact with the filter cloth belt 16 can be made stronger. The pressure rollers 26, 26a, and 26b may be selected as appropriate depending on the properties of sludge, the processing amount, the entrainment position, and the like. The elastic member 65 may have a different property or the same property as the elastic member 66 for crushing sludge, and may be the same or different in thickness.

3.3 Description of Pressure Roller According to Third Modification As shown in FIG. 9, the pressure roller 26 (26 a, 26 b) described above is partially (or entirely) in the longitudinal direction of the outer peripheral surface formed by the filter cloth 68. ) Can be configured as a pressure roller 26c provided with a convex portion 70.

  As shown in FIG. 9, the pressure roller 26c is different from the pressure roller 26 (26a, 26b) except that the pressure roller 26 (26a) is provided with a convex portion 70 arranged in the circumferential direction on the outer peripheral surface thereof. , 26b). The convex portion 70 has a configuration in which, for example, a rod-like member 72 made of a short square bar or a round bar extending in the axial direction of the rotary shaft 60 is fixed to the outer surface of the filter cloth 68 for one round at equal intervals in the circumferential direction. is there. By providing the convex portion 70, when the sludge is caught between the pressure roller 26 c and the filter cloth belt 16, the rotating convex portion 70 bites into the filter cloth belt 16 and the sludge and gets caught. (Driven rotation) becomes more reliable and idling can be prevented more reliably. There may be a plurality of convex portions 70 in the lateral direction, or they may be arranged in a staggered manner. Further, the shape, size, length, and the like of the convex portion 70 may be different from each other.

4). Description of Modified Example of Pressurizing Unit FIG. 10 is a configuration diagram of the pressurized unit 28a according to the modified example, FIG. 10 (A) is a partially sectional front view, and FIG. 10 (B) is a side view. It is. FIG. 11 is a front sectional view showing a state in which the sludge S is crushed by the pressurizing unit 28a shown in FIG.

  As described above, since the pressure roller 26 (26a to 26c) according to the present embodiment includes the elastic member 66, the outer peripheral surface thereof is elastically deformed, and sludge is uniformly distributed in the width direction of the filter cloth belt 16. Can be pressurized. By the way, the filter cloth belt 16 disposed to face the pressure roller 26 (26a to 26c) is formed of a flexible member, and is stretched between rollers 19a and 19e disposed apart from each other. For this reason, depending on the sludge properties, processing amount, etc., as shown in FIG. 12, the filter cloth belt 16 bends in the width direction and the running direction due to the weight of the sludge S or the pressure applied from the pressure roller 26. Cannot be crushed uniformly and flatly, and the shape of the sludge S after crushing may vary, resulting in uneven dewaterability.

  Therefore, as shown in FIGS. 10A and 10B, the lower surface side of the filter cloth belt 16 at a position facing the pressure roller 26 (26a to 26c) is used instead of the pressure unit 28 described above. The pressurizing unit 28a configured to be supported by a support member 74 extending along the width direction of the filter cloth belt 16 may be used.

  The support member 74 has a width (length) that can receive the pressure roller 26 over its entire width, and a thickness (plate thickness) that can sufficiently cover the contact portion between the pressure roller 26 and the filter cloth belt 16. The lower surface of the filter cloth belt 16 can be supported by the upper end surface 74a. The corners of the four sides of the upper end surface 74a may be formed in an R shape in consideration of smooth running of the filter cloth belt 16.

  In the pressure unit 28a, the support member 74 serving as a backing plate is provided on the lower surface of the filter cloth belt 16, so that the weight of the sludge S and the pressure applied from the pressure roller 26 are filtered as shown in FIG. Even when it is applied to the cloth belt 16, the filter cloth belt 16 can be prevented from bending in the width direction and the traveling direction, and the sludge S can be crushed uniformly and flatly. For this reason, if the pressurization part 28a is used, it can avoid effectively that the shape of the sludge S after crushing is stabilized and the dehydrating property is uneven.

5. 5. Description of Modification of Solid-Liquid Separation Device 5.1 Description of Solid-Liquid Separation Device According to First Modification FIG. 13 is a side view showing the configuration of the solid-liquid separation device 12a according to the first modification. FIG. 14 is a plan view of the solid-liquid separator 12a shown in FIG. In FIG. 13, only the solid-liquid separator 12a is shown in the sludge dewatering system 10, the illustration of the dewatering device 14 is omitted, and the same applies to FIGS.

  As shown in FIGS. 13 and 14, the solid-liquid separation device 12 a is different from the solid-liquid separation device 12 shown in FIGS. 1 and 2 in the configuration on the downstream side of the moving mechanism 30. The solid-liquid separator 12 a includes a primary pressurizing unit 80 that pressurizes and flattens sludge conveyed on the upper surface 16 a of the filter cloth belt 16 between the moving mechanism 30 and the pressurizing unit 28. The primary pressurizing unit 80 is gathered at the center by the screws 40 a and 40 b, crushes the sludge discharged from the sludge passage 43, flattenes it flatly, and spreads it in the width direction of the filter cloth belt 16. The primary pressure unit 80 has, for example, the same configuration as the pressure unit 28 (28a) described above, and includes the pressure roller 26 (26a to 26c) having elasticity on the outer peripheral surface thereof.

  In the solid-liquid separator 12a, the sludge which is aggregated and consolidated in the center by the screws 40a and 40b is flattened into a flat plate shape by the pressure roller 26 of the primary pressure unit 80 serving as the first pressure roller. Then, the pressure is dehydrated by the pressure roller 26 of the pressure unit 28 serving as the second pressure roller, and then discharged to the lower dewatering device 14. According to the solid-liquid separator 12a, the sludge concentrated by the screws 40a and 40b is crushed by the two-stage pressure rollers of the primary dewatering unit 80 and the pressure unit 28 and dehydrated to further increase the concentrated concentration of sludge. Can be increased. In addition, since the pressure roller constituting the primary pressure unit 80 is the pressure roller 26 (26a to 26c) which is an elastic roller, the drive source can use the traveling power of the filter cloth belt 16, It is not necessary to add a new drive source or the like, and the dehydrating performance of the apparatus can be improved while reducing costs.

  13 and 14 exemplify a configuration in which the pressure roller 26 (26a to 26c), which is an elastic roller, is used for the primary dewatering unit 80 and the pressure unit 28 (28a). A roller having an outer peripheral surface made of resin or metal that is hard (non-elastic) and provided with a dedicated drive source or the like may be used in the same manner as conventionally used.

  As for the solid-liquid separator 12a, in FIG. 13, compared to the configuration shown in FIG. 1, a roller 19f is added upstream of the roller 19a that supports the filter cloth belt 16, and the filter cloth belt is downstream of the roller 19f. A configuration in which 16 is inclined downward is illustrated. By tilting the filter cloth belt 16, sludge can be introduced more smoothly into the pressurizing unit 28, and the flat sludge discharged from the primary pressurizing unit 80 is raised again by the impact of rolling on the slope. Then, it can be introduced into the pressurizing unit 28 to improve the dehydrating performance in the pressurizing unit 28. Of course, the configuration in which the roller 19f is provided to lower the pressure unit 28 by one step may be applied to the solid-liquid separator 12 shown in FIG.

5.2 Description of Solid-Liquid Separation Apparatus According to Second Modification FIG. 15 is a side view showing the configuration of the solid-liquid separation apparatus 12b according to the second modification, and FIG. 16 shows the solid-liquid separation shown in FIG. It is a top view of the apparatus 12b.

  As shown in FIGS. 15 and 16, the solid-liquid separator 12 b is upstream of the portion where the filter cloth belt 16 is inclined toward the downstream side from the roller 19 f and downstream of the primary pressurizing unit 80. The structure is the same as that of the solid-liquid separator 12a shown in FIG. 13 and FIG. For example, three rod bodies 34 are provided along the width direction of the pressure rollers 26 (26a to 26c) constituting the primary pressure unit 80.

  In the solid-liquid separator 12b, the sludge that has been aggregated and consolidated in the center by the screws 40a and 40b is flattened by the pressure roller 26 of the primary pressure unit 80 serving as the first pressure roller into a flat plate shape. , Each bar 34 can be collected again. The sludge collected by the rod body 34 changes its direction and the shape of the lump in the process of falling while sliding down on the filter cloth belt 16 inclined downward from the roller 19f, and the thicker sludge. Then, it is introduced into the pressure roller 26 (26a to 26c) of the pressure unit 28 (28a) serving as the second pressure roller and dehydrated under pressure. In this way, the sludge compacted by the screws 40a and 40b is crushed and dehydrated by the two-stage pressure rollers of the primary pressure section 80 and the pressure section 28, and once between these two stages of pressure rollers. By providing the rod body 34 that collects the flattened sludge again, the concentrated concentration of the sludge can be further increased. Moreover, by inclining the filter cloth belt 16 on the downstream side of the rod body 34 downward, the thickness of the sludge collected by the rod body 34 can be further increased while the inclined surface is dropped, and the pressurizing portion 28. The dehydration performance can be further enhanced.

  Also in the solid-liquid separator 12b, one of the pressure rollers 26 (26a to 26c) of the primary pressure unit 80 and the pressure unit 28 (28a) is generally used conventionally. Of course, it may be constituted by a hard roller.

5.3 Description of Solid-Liquid Separation Apparatus According to Third Modification FIG. 17 is a side view showing the configuration of the solid-liquid separation apparatus 12c according to the third modification, and FIG. 18 shows the solid-liquid separation shown in FIG. It is a top view of the apparatus 12c.

  As shown in FIGS. 17 and 18, the solid-liquid separation device 12 c is the same as the solid-liquid separation device 12 b shown in FIGS. 15 and 16 except that a pre-pressurization unit 82 is provided on the upstream side of the moving mechanism 30. It is a configuration. The pre-pressurizing unit 82 flatly crushes and smooths the sludge transported on the filter cloth belt 16, spreads it in the width direction of the filter cloth belt 16, and introduces it into the moving mechanism 30. It is preferable to be disposed upstream of the addition nozzle 36e for adding the inorganic flocculant F2. The pre-pressurizing unit 82 has the same configuration as the pressurizing unit 28 (28a) and the primary dehydrating unit 80, and includes the pressure roller 26 (26a to 26c) having elasticity on the outer peripheral surface thereof.

  A rod (second rod) 34 is erected immediately before the pre-pressurizing unit 82. For example, three rod bodies 34 are provided, and two rod bodies 34 are disposed at a predetermined interval on the downstream side of the rod body 34 provided at the center in the width direction of the filter cloth belt 16. In the plan view shown, the three rods 34 are arranged in a substantially triangular shape. Thereby, the sludge introduced into the pre-pressurization part 82 can be collected and raised smoothly.

  In the solid-liquid separator 12c, as described above, the rod body 34 is erected on the upstream side of the screws 40a and 40b, and the filter cloth belt 16 is conveyed between the rod body 34 and the screws 40a and 40b. A pre-pressurizing unit 82 including a pressure roller 26 (26a to 26c) serving as a third pressure roller (pre-pressure roller) that pressurizes and dehydrates the sludge is provided. For this reason, after collecting sludge with the rod 34, it can introduce | transduce into screw 40a, 40b, after making it flat with the pre-pressurization part 82, and can raise the concentration density | concentration of sludge further. That is, the sludge collected by being aligned by the rods 34 is leveled by the pressure roller 26 of the pre-pressing section 82, and after the inorganic flocculant F2 is added, the sludge is kneaded by the screws 40a and 40b. It is consolidated in the center and becomes a lump. Subsequently, the lump sludge is leveled again by the pressure roller 26 (26a to 26c) of the primary pressure unit 80 serving as the first pressure roller, and then gathered again by the rods 34. Then, it slides down on the filter cloth belt 16 inclined downward from the roller 19f, and is introduced into the pressure roller 26 (26a to 26c) of the pressure unit 28 (28a) serving as the second pressure roller and pressurized. Dehydrated.

  Also in the solid-liquid separation device 12c, any one of the pressure roller 26 (26a to 26c) of the pre-pressure unit 82, the primary pressure unit 80, and the pressure unit 28 (28a) is conventionally conventionally used. Of course, it may be composed of a hard roller similar to the one used.

5.4 Description of Solid-Liquid Separation Device According to Fourth Modification FIG. 19 is an explanatory side view showing the configuration of the solid-liquid separation device 12d according to the fourth modification, and includes rollers 19b and 19c, a filtrate receiving tray 32a, 32b, the coagulation mixing tank 24, the first chemical injection device 38, the second chemical injection device 36, and the like are omitted, and the same applies to FIG.

  As shown in FIG. 19, the solid-liquid separator 12 d has the solid-liquid separation shown in FIGS. 17 and 18 except that an initial pressurizing unit 84 is provided instead of the rod 34 on the upstream side of the prepressurizing unit 82. The configuration is substantially the same as that of the device 12c. It should be noted that the arrangement of the pressure unit 28 and the roller 19a on the downstream side is slightly different in the solid-liquid separation device 12d compared to the solid-liquid separation device 12c and the like, and is more downstream than the pressure roller 26 constituting the pressure unit 28. A roller 19a is disposed.

  The initial pressurizing unit 84 flatly crushes and smoothes the sludge conveyed on the filter cloth belt 16 and spreads it in the width direction of the filter cloth belt 16 before introducing it to the pre-pressurizing unit 82. The pressure unit 28 (28a), the primary dehydration unit 80, and the pre-pressurization unit 82 are configured in the same manner, and the pressure roller 26 (26a to 26c) having elasticity is provided on the outer peripheral surface thereof.

  In the solid-liquid separator 12d, the pressure roller 26 serving as a fourth pressure roller (initial pressure roller) that pressurizes and dewaters the sludge conveyed on the filter cloth belt 16 on the upstream side of the pre-pressure unit 82. An initial pressurizing unit 84 including (26a to 26c) is provided. For this reason, since the sludge can be introduced to the screws 40a and 40b after being flattened to some extent by the initial pressurizing unit 84 and further flattened by the pre-pressurizing unit 82, the concentrated concentration of sludge can be further increased. .

  Also in the solid-liquid separator 12d, any one of the pressure rollers 26 (26a to 26c) of the initial pressure unit 84, the pre-pressure unit 82, the primary pressure unit 80, and the pressure unit 28 (28a). Of course, it may be constituted by a hard roller in the same manner as conventionally used.

5.5 Description of Solid-Liquid Separation Device According to Fifth Modification FIG. 20 is an explanatory side view showing the configuration of the solid-liquid separation device 12e according to the fifth modification.

  As shown in FIG. 20, the solid-liquid separation device 12 e is the same as the solid-liquid separation device shown in FIG. 19 except that a front moving mechanism 86 is provided instead of the initial pressurization unit 84 upstream of the pre-pressurization unit 82. The configuration is substantially the same as 12d. The front moving mechanism 86 moves the sludge transported on the filter cloth belt 16 in a direction crossing the transport direction, consolidates it in the center, and introduces it into the pre-pressurizing unit 82. It is set as the structure similar to the mechanism 30, and is provided with screws 40a and 40b.

  In the solid-liquid separation device 12e, a screw 40a is provided by providing a front moving mechanism 86 including screws 40a and 40b that move and compact sludge conveyed on the filter cloth belt 16 on the upstream side of the pre-pressurizing unit 82. , 40b and a plurality of combinations (two in FIG. 20) of elastic rollers (pressure roller 26). As a result, after the sludge is consolidated by the front moving mechanism 86, the sludge can be introduced into the screws 40a and 40b after further flattening by the pre-pressurizing unit 82, and thus the concentrated concentration of sludge can be further increased.

  By the way, as shown in the explanatory diagrams using arrows in FIGS. 19 and 20, in the solid-liquid separators 12d and 12e, the moisture content of the sludge is high on the upstream side in the traveling direction of the filter cloth belt 16. Therefore, the amount (volume) of sludge is large, and the amount of sludge gradually decreases toward the downstream side, and the same applies to the other solid-liquid separators 12 and 12a to 12c.

  Therefore, in consideration of such a change in the amount of sludge in the conveying direction, pressure rollers 26 (26a to 26c) serving as elastic rollers are provided as in the solid-liquid separators 12a to 12e shown in FIGS. In the case of a configuration in which a plurality of filter cloth belts 16 are arranged in the running direction, the elasticity of the outer peripheral surface (the elastic modulus of the elastic member 66 or the elastic modulus of the entire roller outer surface) may be changed for each pressure roller 26, for example, It is preferable to increase the elastic modulus of the downstream side from the upstream side and harden the elasticity. In the upstream pressure roller 26 with a large amount of sludge, for example, the pressure roller 26 of the initial pressure unit 84 in the solid-liquid separator 12d shown in FIG. 19, the outer circumference is reduced by reducing the elastic modulus and softening the elasticity. The sludge can be received and reliably crushed while sufficiently elastically deforming the surface. On the other hand, in the downstream pressure roller 26 with a small amount of sludge, for example, the pressure roller 26 of the pressure unit 28 in the solid-liquid separator 12d shown in FIG. 19, a small amount is obtained by increasing the elastic modulus and hardening the elasticity. Even sludge can be crushed with sufficient pressure.

  In a similar manner, in the case of a configuration in which a plurality of pressure rollers 26 (26a to 26c) serving as elastic rollers are arranged as in the solid-liquid separators 12a to 12e shown in FIGS. The roller diameter (outer diameter) may be changed. For example, the roller diameter on the downstream side may be smaller than that on the upstream side. The upstream pressure roller 26 that requires a large pressure to crush due to a large amount of sludge, such as the pressure roller 26 of the initial pressure unit 84 in the solid-liquid separator 12d shown in FIG. 19, has a large outer diameter. By doing so, the sludge can be crushed with sufficient pressurizing force by a large torque. On the other hand, in the pressure roller 26 on the downstream side where the amount of sludge is reduced and the pressure for crushing may be small, for example, the pressure roller 26 of the pressure unit 28 in the solid-liquid separator 12d shown in FIG. By doing so, sludge can be sufficiently crushed while reducing the load applied to the drive source 17 of the filter cloth belt 16 during the driven rotation by the filter cloth belt 16, and the drive source 17 can be reduced in size.

  Further, as in the case of the solid-liquid separators 12a to 12e shown in FIGS. 13 to 20, when a plurality of pressure rollers 26 (26a to 26c) serving as elastic rollers are arranged, pressure is applied to each pressure roller 26. The gap between the roller 26 and the filter cloth belt 16 may be changed. For example, the gap on the downstream side from the upstream side may be made smaller. That is, in the upstream pressure roller 26 having a large amount of sludge, for example, the pressure roller 26 of the initial pressure unit 84 in the solid-liquid separator 12d shown in FIG. By enlarging, even a large amount of sludge can be reliably received and crushed. On the other hand, in the pressure roller 26 on the downstream side with a small amount of sludge, for example, the pressure roller 26 of the pressure unit 28 in the solid-liquid separator 12d shown in FIG. 19, the gap between the upper surface 16a of the filter cloth belt 16 is made small. By doing so, even a small amount of sludge can be crushed with sufficient pressure.

  The settings of the elasticity, the roller diameter and the gap in each elastic roller may be used in combination. For example, the elasticity of the pressure roller 26 (26a to 26c) on the downstream side from the upstream side is hardened. The roller diameter may be reduced and the gap may be reduced.

  Moreover, like the solid-liquid separators 12a to 12e shown in FIGS. 13 to 20, the pressure roller 26 (26a to 26c) which is an elastic roller, and the moving mechanism 30 (screws 40a and 40b and the sludge mixing device). The guide plates 42a, 42b) and the rods 34 are alternately arranged. With this configuration, the pressure roller 26 on the downstream side is more elastic than the pressure roller 26 on the upstream side, and the roller diameter is reduced. And if it is set as the structure which made the clearance gap small, the concentration density | concentration of sludge can be raised still more efficiently.

  It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that the present invention can be freely changed without departing from the gist of the present invention.

  For example, FIG. 2 illustrates a configuration in which the screws 40a and 40b and the guide plates 42a and 42b constituting the moving mechanism 30 are installed in a direction perpendicular to the sludge transport direction by the filter cloth belt 16, but these screws 40a and 40b are illustrated. And the guide plates 42a and 42b are good also as the attitude | position inclined with respect to the conveyance direction of sludge. Of course, the moving mechanism 30 may be configured by a single screw extending in the width direction of the filter cloth belt 16.

DESCRIPTION OF SYMBOLS 10 Sludge dehydration system 12, 12a-12e Solid-liquid separator 14 Dehydrator 16, 20, 22 Filter cloth belt 17 Drive source 17a, 23, 60 Rotating shaft 18 Filtration part 24 Coagulation mixing tank 26, 26a-26c Pressure roller 28 , 28a Pressurizing unit 30 Moving mechanism 34 Rod body 36 Second medicine injection device 38 First medicine injection device 40a, 40b Screw 42a, 42b Guide plate 43 Sludge passage 64 Hard member 66 Elastic member 68 Filter cloth 70 Convex portion 72 Rod-like member 74 Support member 80 Primary pressurizing part 82 Pre-pressurizing part

Claims (15)

A belt that travels by a driving force from a driving source and conveys sludge; and a pressure roller that is disposed opposite to the upper surface of the belt and presses the sludge conveyed on the upper surface between the upper surface and the sludge. A solid-liquid separation device for dehydrating and solid-liquid separation,
The pressure roller is disposed on the outer peripheral side of the rotary shaft, and is elastically supported on the outer peripheral side of the rotary shaft. The rotary shaft is freely rotatable about a direction orthogonal to the sludge conveyance direction by the belt. A solid liquid characterized in that at least a part of the outer peripheral surface is in contact with the upper surface of the belt in a state where no sludge is placed on the upper surface of the belt. Separation device. The solid-liquid separator according to claim 1,
The pressure roller has a hard member provided at both ends of the rotating shaft, and the elastic member is provided between the hard members at both ends. The solid-liquid separator according to claim 2,
A solid-liquid separation device, wherein a second elastic member is provided on an outer peripheral surface of the hard member. The solid-liquid separator according to claim 1,
The pressure roller is a solid-liquid separator, wherein the elastic member is provided on an outer peripheral surface of the rotating shaft. In the solid-liquid separation device according to any one of claims 1 to 4,
An outer peripheral surface of the pressure roller is formed of a flexible sheet-like member. The solid-liquid separator according to claim 5,
The belt is a filter body capable of filtering water contained in the sludge,
The said sheet-like member is formed with the same raw material as the said filter body, The solid-liquid separator characterized by the above-mentioned. The solid-liquid separator according to claim 1,
A solid-liquid is provided on the upstream side of the pressure roller, and includes a screw that extends in a direction intersecting with the conveying direction of the sludge by the belt and moves the sludge in a direction intersecting with the conveying direction by the belt by the rotation thereof. Separation device. The solid-liquid separator according to claim 7,
A solid-liquid separation device comprising a second pressure roller that presses sludge conveyed on the upper surface of the belt between the upper surface and the lower surface of the pressure roller. The solid-liquid separator according to claim 8,
A solid-liquid separation characterized in that a rod that comes into contact with the sludge conveyed on the upper surface of the belt is erected at a position downstream of the pressure roller and upstream of the second pressure roller. apparatus. In the solid-liquid separation device according to any one of claims 7 to 9,
A second rod body that contacts the sludge conveyed on the upper surface of the belt is erected on the upstream side of the screw, and the sludge conveyed on the upper surface of the belt between the second rod body and the screw. A solid-liquid separation device comprising a third pressure roller that pressurizes between the upper surface and the upper surface. In the solid-liquid separation device according to any one of claims 1 to 4,
A solid-liquid separation device, wherein a convex portion is provided on an outer peripheral surface of the pressure roller. In the solid-liquid separation device according to any one of claims 1 to 4,
A solid-liquid separation device comprising a support member that extends along the width direction of the belt and supports the lower surface side of the belt at a position on the lower surface side of the belt facing the pressure roller. . The solid-liquid separator according to claim 1,
A plurality of the pressure rollers are installed along the sludge transport direction by the belt,
A solid-liquid separator characterized in that elasticity, outer diameter, or a gap between the pressure roller and the upper surface of the belt is made different for each pressure roller. The solid-liquid separator according to claim 13,
When making the elasticity different for each pressure roller, increase the elastic modulus of the pressure roller on the downstream side from the upstream side,
When the outer diameter is different for each pressure roller, the outer diameter of the pressure roller downstream from the upstream side is reduced,
When the gap between the upper surface of the belt is different for each pressure roller, the solid-liquid separation is characterized in that the gap between the pressure roller downstream from the upstream side and the upper surface of the belt is reduced. apparatus. A pressure roller disposed opposite to the upper surface of the belt that conveys sludge by running with a driving force from a drive source, and dewatering by pressing the sludge conveyed on the upper surface with the upper surface;
A pressure roller comprising: a rotary shaft; and an elastic member that is disposed on an outer peripheral side of the rotary shaft and elastically supports an outer peripheral surface of the pressure roller.

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