JP2011005362A - Slurry treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slurry treatment apparatus capable of uniformly concentrating slurry into high concentration.SOLUTION: The slurry treatment apparatus 1 includes: a concentration tank 2 for separating the slurry A into concentrated slurry B obtained by concentrating the slurry A and a supernatant C by settling solid particles in slurry A; a nearly funnel-like concentration tank body 21 having a discharge port 24 for discharging the concentrated slurry B on an inner bottom part 23, a cylindrical drum 22 for storing the supernatant C in the upper part, and an over flow part 25 for discharging the supernatant C in the upper par; a slurry supply path 4 for supplying the slurry A to the inside of the concentration tank body 21; and a stirring device 6 arranged freely rotatably inside the concentration tank body 21. The stirring device 6 has a stirring blade 61 for allowing to flow upward the concentrated slurry B sinking from the upper side of the concentration tank body 21, a rotary shaft 63 on which the stirring blade 61 is provided and a stirring drive motor 62 for rotating the rotary shaft 63.

Description

  The present invention is a slurry concentration tank capable of concentrating a slurry in which various fine solid particles such as incineration fly ash, metal, and debris collected at the time of incineration such as municipal waste are suspended in water to a high concentration. It is related with the slurry processing apparatus provided with.

  Conventionally, there are various types of slurries depending on industrial purposes and objects. The purpose of concentrating the slurry, the processing method and the processing apparatus are also various. For example, as a method for concentrating a slurry containing a solid content such as a metal, the slurry concentrating method described in Patent Document 1 is known.

FIG. 6 is a schematic view showing an example of a slurry concentration tank used in a conventional slurry processing apparatus.
As shown in FIG. 6, in the slurry concentration method of Patent Document 1, the slurry A100 obtained by adding a flocculant to the slurry in the aggregation reaction tank and stirring the slurry A100 is solidified in the slurry A100 in the slurry concentration tank 100 (sedimentation tank). A concentrated slurry B100 obtained by concentrating particles (powder such as sludge) by sedimentation is obtained.

  Thus, when separating solid particles from slurry A100 in which solid particles and water are mixed, or when obtaining concentrated slurry B100 obtained by concentrating slurry A100, slurry concentration tank 100 is used. The slurry concentrating tank 100 has a discharge port 220 in the inner bottom portion 210 and a concentrating tank main body 200 having a tapered surface 230 inclined gently from the periphery of the discharge port 220 toward the discharge port 220, and the inside of the concentrating tank main body 200. A mud collecting rake 300 disposed at a predetermined interval on the inner bottom part 210 of the slag and rotated by the driving motor 310 to collect the concentrated slurry B100, and a center installed at an upper central part in the concentrating tank body 200. A well 600, a supply pipe 400 for supplying the slurry A100 to the upper part in the center well 600, and an overflow part 500 installed near the upper end in the concentration tank body 200 to drain the supernatant C100 to the outside of the concentration tank body 200. And is composed of.

  In such a slurry concentration tank 100, the solid particles in the slurry A100 are settled on the tapered surface 230 of the concentration tank main body 200 to be separated into solid particles and liquid to obtain a concentrated slurry B100. Yes. The angle θ100 of the tapered surface 230 is generally formed to have a gentle inclination of about 160 to 130 degrees for the purpose of concentrating the slurry A100. Thus, by making the tapered surface 230 a gentle inclined surface, the solid particles are less likely to flow downward on the tapered surface 230 and less likely to flow into the discharge port 220, thereby obtaining a concentrated slurry A100. The height of the slurry concentration tank 100 is suppressed from increasing.

JP 2006-212569 A (paragraphs 0051 to 0055)

  However, in the slurry concentrating tank 100 as shown in Patent Document 1 and FIG. 6, since the angle θ100 of the tapered surface 230 of the concentrating tank body 200 is formed on a gentle slope of about 160 to 130 degrees, mud collection is performed. Even if the rake 300 rotates along the inner bottom portion 210, the solid particles B200 that have settled on the inner bottom portion 210 do not flow smoothly on the tapered surface 230 toward the lowermost side of the center, and gather in an uneven state. Mud. Therefore, there is a problem that the concentrated slurry B100 obtained from the slurry concentration tank 100 is concentrated to a non-uniform concentration.

  As a means for solving the above problem, the solid particles B200 that have settled on the inner bottom portion 210 do not accumulate on the tapered surface 230, and slide down the tapered surface 230 to the discharge port 220. It is conceivable that the angle of the tapered surface 230 is formed on a steep slope so as to fall inside. In this case, by forming the angle of the tapered surface 230 on a steep slope, the solid particles B200 flow into and accumulate in the discharge port 220, the discharge port 220 is clogged, and the overall height of the slurry concentration tank 100 is increased. was there.

  For this reason, conventionally, as described above, the angle θ100 of the tapered surface 230 is formed on a gentle slope so that the solid particles hardly flow. In the past, in order to improve the dewatering capacity of the dehydrator, it has been desired to concentrate the slurry A100 to a high concentration in the slurry concentration tank 100. However, the problem described in paragraph 0008 has occurred. A high concentration slurry could not be obtained.

  Then, this invention is made | formed in view of the said problem, and makes it a subject to provide the slurry processing apparatus which can concentrate a slurry uniformly to high concentration.

  In order to solve the above-described problem, the slurry processing apparatus according to claim 1 includes a slurry concentration tank that settles solid particles in the slurry and separates the slurry into a concentrated slurry obtained by concentrating the slurry and a supernatant. In the slurry processing apparatus, the inner bottom portion has a discharge port for discharging the concentrated slurry, and the upper portion has a cylindrical body portion in which the supernatant liquid is stored, and an overflow portion for discharging the supernatant liquid. A substantially funnel-shaped concentrating tank main body, a slurry supply path for supplying the slurry into the concentrating tank main body, and a stirrer disposed rotatably inside the concentrating tank main body, A plurality of stirring blades for flowing upward the concentrated slurry that has settled from above in the concentration tank body, a rotating shaft provided with the plurality of stirring blades, and a stirring for rotating the rotating shaft Characterized in that it has a dynamic motor.

According to such a configuration, the slurry processing apparatus is configured such that the concentrated slurry is stirred and circulated on the inner bottom portion and flows by causing the stirring blade in the concentration tank body to rotate and causing the concentrated slurry to flow upward. As a result, the solid particles that have settled on the inner bottom part are not easily deposited on the inner bottom part.The solid particles flow down the steep slope on the inner bottom part due to the flow of the concentrated slurry circulating on the inner bottom part and the weight of the solid particles. It tends to flow toward the side and is collected in a relatively uniform and compact mud state in the inner bottom and continues to circulate in the inner bottom.
And the water | moisture content in a slurry is isolate | separated to the upper side of a solid particle, becomes a supernatant liquid, and is discharged | emitted outside from an overflow part. For this reason, the slurry supplied to the slurry concentration tank becomes a concentrated slurry in which the solid particles are gathered in a dense mud state by the amount of the supernatant liquid removed and uniformly concentrated to a high concentration, It is discharged from the outlet to the concentration tank body.

  The slurry processing apparatus according to claim 2 is the slurry processing apparatus according to claim 1, wherein the solid particles that have sunk on the inner bottom face downward on the inner bottom. It is formed in the shape of an inverted cone having an inclination angle that flows.

  According to such a configuration, the slurry processing apparatus sinks onto the inverted conical inner bottom by forming the inclination angle of the inner bottom of the concentration tank body at an angle that flows downward on the inner bottom. The solid particles can be slid under their own weight on the upper surface of the inclined inner bottom portion toward the lower side.

  The slurry processing apparatus of Claim 3 is a slurry processing apparatus of Claim 1 or Claim 2, Comprising: The said stirring apparatus is arrange | positioned above the said inner bottom part of the said concentration tank main body at predetermined intervals. And a scraper that is fixed to the rotating shaft and scrapes off the concentrated slurry that has settled on the inner bottom by rotating the stirring drive motor.

  According to such a configuration, since the solid particles in the concentrated slurry that have settled on the inner bottom portion of the concentration tank body are scraped off by the scraper, even if they are deposited on the inner bottom portion, they are only deposited in a uniform layer thinly. It does not accumulate in a mountain-like uneven state.

  The slurry processing apparatus according to claim 4 is the slurry processing apparatus according to any one of claims 1 to 3, wherein the inner bottom portion has a lowermost end portion of a central portion, and the discharge port. A transfer blade fixed to the lower end of the rotating shaft, rotating in the same direction as the scraper, and sending the concentrated slurry in the storage portion to the discharge port. Is arranged.

  According to such a configuration, the rotating shaft of the stirring device rotated by the stirring drive motor is provided with a storage portion having a discharge port at the lowermost end portion of the concentrating tank body, and the conveying blade is provided in the storage portion. ing. For this reason, the solid particles contained in the slurry supplied into the slurry concentration tank smoothly flow from the inner bottom portion to the storage portion and the discharge port, and are sent out of the concentration tank body from the discharge port.

  The slurry processing apparatus according to claim 5 is the slurry processing apparatus according to claim 4, wherein the concentration tank body includes a level sensor that detects a slurry level of the concentrated slurry that has settled on the inner bottom. A discharge pump for sucking the concentrated slurry in the reservoir and sending it to the downstream side, and a slurry transfer pipe communicating with the discharge port, and the discharge pump is detected by the level sensor The concentrated slurry is rotated by a driving signal based on a slurry level of the concentrated slurry.

  According to this configuration, the discharge pump is driven by the drive signal from the level control device that controls the slurry level of the concentrated slurry to be a predetermined level based on the slurry level of the concentrated slurry detected by the level sensor. For this reason, the concentrated slurry of the desired concentration can be obtained by adjusting the high concentration of the concentrated slurry by appropriately discharging the concentrated slurry at the inner bottom in the concentration tank body from the discharge port.

  The slurry processing apparatus of Claim 6 is a slurry processing apparatus of Claim 5, Comprising: The said concentration slurry sent to the downstream of the said slurry conveyance pipe by the said discharge pump is the water | moisture content in this concentration slurry. It is characterized by being dehydrated by a dehydrator that dehydrates the water.

  According to this configuration, the concentrated slurry concentrated in the slurry concentrating tank is sent from the slurry conveying pipe to the downstream dehydrator by the discharge pump, and further, the moisture in the concentrated slurry is dehydrated and concentrated to reduce the concentration. It becomes a hydrated flake-shaped dehydrated cake.

  According to the slurry processing apparatus of the first aspect of the present invention, a concentrated slurry obtained by uniformly concentrating the slurry at a high concentration can be obtained.

  According to the slurry processing apparatus of the second aspect of the present invention, the solid particles settled on the inverted conical inner bottom are slid under the own weight toward the lower side on the upper surface of the inclined inner bottom so that the solid particles Accumulation on the bottom can be eliminated.

  According to the slurry processing apparatus of the third aspect of the present invention, the solid particles in the concentrated slurry that have settled on the inner bottom portion of the concentration tank body are scraped off by the scraper and deposited in a mountain-like uneven state on the inner bottom portion. It is possible to prevent the concentration of the concentrated slurry from becoming nonuniform.

  According to the slurry processing apparatus according to claim 4 of the present invention, the solid particles in the slurry supplied into the slurry concentrating tank are smoothly flowed from the inner bottom of the concentrating tank main body to the storage section and the discharge port, The concentrated concentrated slurry can be easily sent out of the main body of the concentration tank without clogging from the discharge port.

  According to the slurry processing apparatus of the fifth aspect of the present invention, it is possible to always obtain a concentrated slurry having a uniform concentration while keeping the amount of solid particles contained in the slurry in the slurry concentration tank constant.

  According to the slurry processing apparatus of the sixth aspect of the present invention, the concentrated slurry concentrated in the slurry concentrating tank can be sent to the dehydrator by the discharge pump to further obtain a low-moisture flaky dehydrated cake. At the same time, the dewatering capacity of the dehydrator can be improved.

It is the schematic which shows the slurry processing apparatus which concerns on embodiment of this invention. It is a general | schematic expanded sectional view which shows the slurry concentration tank of the slurry processing apparatus which concerns on embodiment of this invention. It is an enlarged view of the lower part of the slurry concentration tank shown in FIG. It is a schematic enlarged plan view which shows the slurry concentration tank of the slurry processing apparatus which concerns on embodiment of this invention. It is a flowchart which shows the action | operation of the level control apparatus of the slurry processing apparatus which concerns on embodiment of this invention. Although it shows an example of the slurry concentration tank currently used for the conventional slurry processing apparatus, it is a schematic diagram.

Hereinafter, embodiments for carrying out the invention will be described with reference to FIGS.
In addition, the slurry A concentrated in the slurry processing apparatus 1 has various fine solid particles such as incineration fly ash, metal, ceramic, sludge, and debris collected during incineration of municipal waste suspended in water. The type of the slurry A is not particularly limited as long as it concentrates the slurry A and contains solid particles. Hereinafter, an example of the present invention will be described by taking as an example the case of concentrating slurry A containing incinerated fly ash as solid particles.
First, before explaining the slurry processing apparatus 1, the incineration fly ash and the slurry A will be explained.

≪Description of incineration fly ash and slurry≫
Incineration fly ash is powdered solid particles made of highly alkaline high temperature incineration fly ash having a hydrogen ion concentration of pH 11 to pH 13, and contains chlorine compounds and heavy metals (for example, zinc Zn, lead Pb, cadmium Cd, etc.) Has been.
In order to recycle the incinerated fly ash, the slurry A is washed with about 5 to 10 times water and the hydrogen ion concentration is adjusted to pH 9 to 10 with a strong acid solution for the purpose of eluting the contained inhibitor. Made up of turbid liquid. The slurry A is first transferred to the aggregation reaction tank 3 shown in FIG.

<< Configuration of slurry processing equipment >>
The slurry processing apparatus 1 includes a flocculation reaction tank 3 that causes the slurry A to flocculate, a slurry supply path 4 that supplies the slurry A in the agglomeration reaction tank 3, and the slurry A that is supplied by the slurry supply path 4 A slurry concentration tank 2 for obtaining a concentrated slurry B separated and concentrated, a stirring device 6 provided in the slurry concentration tank 2, a slurry discharge device 7 for sucking the concentrated slurry B in the slurry concentration tank 2, and , A level control device 8 for adjusting the slurry level of the concentrated slurry B (solid particles) in the slurry concentration tank 2, a dehydrator 9 to which the concentrated slurry B sucked by the slurry discharge device 7 is supplied, a power source 10, It has.

≪Configuration of agglomeration reaction tank≫
As shown in FIG. 1, the agglomeration reaction tank 3 is a reaction tank in which a polymer flocculant F is added to the slurry A to cause an agglomeration reaction. In the flocculation reaction tank 3, a flocculation tank 31 for storing the slurry A, a slurry inlet 32 through which the slurry A is supplied to the flocculation tank 31 by a supply pump or the like (not shown), and a polymer flocculant F are supplied by a supply pump or the like ( A coagulant receiving port 33 supplied to the coagulation tank 31, a drain port 34 for discharging the slurry A and the like to the outside of the coagulation tank 31, and a coagulation reaction for stirring the slurry A in the coagulation tank 31. A tank scraper 35, a coagulation reaction tank stirring motor 36 for rotating the coagulation reaction tank scraper 35, a slurry outlet 37 for discharging the slurry A in the upper layer in the coagulation tank 31 to the outside of the coagulation tank 31, It is mainly prepared.

The aggregation tank 31 is a bottomed cylindrical tank whose upper opening is closed by a liquid overflow prevention lid 38. In the agglomeration tank 31, a slurry inlet 32, a flocculant receiving port 33, and a drain port 34 are installed in the lower layer part, a slurry outlet 37 is installed in the upper layer part, and a scraper 35 for the aggregation reaction tank is installed in the middle layer part. Is arranged.
The slurry inlet 32, the flocculant receiving port 33, and the drain port 34 are arranged in different positions at the same height in the lower layer of the coagulation tank 31.

The agglomeration reaction tank scraper 35 includes a rotation shaft 35a rotated by the agitation reaction tank stirring motor 36, a bearing portion 35b provided at the lower end of the rotation shaft 35a, and a scraper support member 35d provided on the rotation shaft 35a. And a scraper body 35c fixed to the rotary shaft 35a with the scraper support member 35d interposed therebetween.
The rotating shaft 35a extends vertically along the center line of the aggregation tank 31, the lower end is pivotally supported by the bearing portion 35b, and the upper end is supported by the gantry 35e.
The bearing portion 35 b is installed at the center of the inner bottom of the aggregation tank 31.
The scraper main body 35 c is composed of two rod-like members extending up and down parallel to the rotation shaft 35 a, and is disposed so as to rotate along the inner wall of the aggregation tank 31.
The scraper support member 35d is a member for fixing the two scraper main bodies 35c arranged at symmetrical positions with respect to each other, and is installed at two locations, a lower portion of the rotating shaft 35a and an intermediate layer portion of the rotating shaft 35a. Has been.
The gantry 35 e is a member that is placed on the liquid overflow prevention lid 38 and holds the agitation reaction tank agitation motor 36.

The agglomeration reaction tank agitation motor 36 is a motor drive device incorporating a speed reduction mechanism that reduces the rotation of the rotor and transmits the rotation to the rotary shaft 35 a, and is disposed at the center of the upper surface of the liquid overflow prevention lid 38.
The slurry outlet 37 is disposed above the aggregation tank 31 in order to discharge the slurry A in the aggregation tank 31 to the outside of the aggregation tank 31. The slurry A overflowing from the slurry outlet 37 is provided so as to flow into the slurry supply path 4.

≪Configuration of slurry supply path≫
The slurry supply path 4 is a supply path for supplying the slurry A in the aggregation reaction tank 3 into the concentration tank body 21. The slurry supply path 4 is connected to the slurry outlet 37 of the agglomeration reaction tank 3 on the upstream side and connected to the upper eccentric position of the inner cylinder 5 disposed in the slurry concentration tank 2 on the upstream side and from the upstream side to the downstream side. It is arranged so as to be inclined downward. An opening end 4a (see FIG. 4) on the downstream side of the slurry supply path 4 is arranged at a position shifted from the center of the inner cylinder 5 in plan view in the upper part of the inner cylinder 5. For this reason, the slurry A discharged from the slurry supply path 4 descends while spirally winding in the inner cylinder 5 downward (arrow a direction).

≪Configuration of slurry concentration tank≫
As shown in FIG. 2, the slurry concentrating tank 2 sediments the solid particles in the slurry A supplied from the slurry supply path 4 by gravity, and sediments the concentrated slurry B having a high concentration of the slurry A and the solid particles. The liquid C thus purified and the dilute slurry D whose concentration of the slurry A is intermediate between the concentrated slurry B and the supernatant C are subjected to solid-liquid separation. It is a tank for obtaining. The slurry concentrating tank 2 includes a concentrating tank main body 21 that forms the main body of the slurry concentrating tank 2, the slurry supply path 4, an inner cylinder 5 disposed in the center of the concentrating tank main body 21, slurry A, and concentrated slurry. A stirrer 6 that stirs B (solid particles), and a level control device 8 (see FIG. 1) for adjusting the slurry level of the concentrated slurry B (solid particles) in the concentration tank body 21 to a predetermined concentration. It is prepared for.
The slurry concentration tank 2 is also referred to as a settling tank, a settling tank, or a separation tank.

≪Concentration tank configuration≫
The concentration tank body 21 is formed in a substantially funnel shape having an opening at the upper end, and is a tank body for obtaining the concentrated slurry B by sedimenting the contained solid particles while temporarily storing the slurry A. . The concentrating tank body 21 includes a barrel portion 22 formed in a cylindrical shape, a tapered inner bottom portion 23 continuously formed below the barrel portion 22, a storage portion 26 formed at a lower end portion of the inner bottom portion 23, A discharge port 24 formed on the inner wall of the reservoir 26, a weir 27 formed on the inner upper edge of the concentration tank body 21, and a supernatant liquid recovery path 28 that forms a flow path for the supernatant C overflowing from the weir 27 The overflow portion 25 from which the supernatant C flows out from the supernatant recovery path 28 and the support column 29 that supports the concentration tank body 21 are provided.
An inner cylinder 5, a rotating shaft 63, a stirring blade 61, a scraper 64, a transport blade 65, and a level sensor 71 are provided inside the concentration tank body 21. Outside the concentration tank main body 21, the slurry supply path 4, a slurry transport pipe 73 connected to the discharge port 24, a pipe (not shown) connected to the overflow unit 25, a level control device 8, and the like are installed. Has been. In addition, the concentration tank main body 21 may close | close the upper side opening part with the cover body.

  As shown in FIG. 2, the trunk | drum 22 consists of a cylindrical member formed toward the up-down direction. The body 22 has an opening at the upper end and a cone-shaped inner bottom 23 at the lower end. In the trunk portion 22, the supernatant C is stored in the upper part, the dilute slurry D is stored in the lower part, and the concentrated slurry B having a predetermined concentration of mud is stored in the lowermost part. A lower end portion of the inner cylinder 5, a lower end portion of the level sensor 71, and a body scraping portion 64 b of the scraper 64 are disposed at the lower end portion of the body portion 22.

  As shown in FIG. 3, the inner bottom part 23 is a part for temporarily retaining solid particles that have settled from above the concentration tank body 21 to secure a slurry zone in a certain consolidated state on the inner bottom part 23. It is. The inner bottom portion 23 is formed in an inverted conical shape having an inclination angle θ1 in which solid particles that have settled on the inner bottom portion 23 easily flow downward on the inner bottom portion 23. The inclination angle θ1 of the inner bottom portion 23 is within 120 to 60 degrees, preferably 105 to 75 degrees, and more preferably about 90 to 80 degrees. The inner bottom portion 23 is formed in a bowl shape on a steep slope so that solid particles settled on the inner bottom portion 23 slide down downward (in the direction of arrow d) toward the central storage portion 26.

The storage part 26 is formed in a bottomed cylindrical shape at the lower end of the central part of the inner bottom part 23, and is a part where the concentrated slurry B is temporarily stored, and is formed in a substantially bottomed cylindrical shape. A conveying blade 65 is rotatably disposed in the storage portion 26.
The discharge port 24 is a discharge port that is formed on the inner wall portion of the reservoir 26 and discharges the concentrated concentrated slurry B to the outside of the concentration tank body 21.

The weir 27 shown in FIG. 2 is a portion where, when the inside of the concentration tank main body 21 is filled with the slurry A, what is lighter in weight than solid particles such as the supernatant C and scum overflows outside the concentration tank main body 21; It consists of a plurality of triangular weirs formed over the entire upper edge periphery of the body 22.
The supernatant liquid recovery path 28 is a channel having a concave cross section formed on the outer periphery of the weir 27, and is formed so that the supernatant C overflowing from the weir 27 flows toward the overflow part 25.
The overflow portion 25 is connected to a pipe (not shown) for sending the supernatant C overflowing from the supernatant recovery path 28 to a treatment tank installed outside the slurry concentration tank 2.

≪Configuration of inner cylinder≫
The inner cylinder 5 is a center well from which the slurry A flowing from the slurry supply path 4 is discharged, and is a cylinder suspended from the upper part of the central part in the concentration tank body 21 to the lower end central part of the body part 22. It consists of a tube. Since the slurry supply path 4 is arranged so as to be shifted from the center with respect to the inner cylinder 5, the slurry A sent into the inner cylinder 5 is guided by the inner wall surface of the inner cylinder 5 and spirally vortexed. It comes to descend while winding.

≪Configuration of stirring device≫
The stirring device 6 scrapes off the concentrated slurry B that has settled on the inner bottom portion 23 and stirs and stirs the concentrated slurry B in the inner bottom portion 23 so that the solid particles are uniformly deposited in the slurry concentration tank 2 without being deposited. It is an apparatus for making it flow upward from the bottom so as to circulate and flow in a state of a proper concentration. The stirring device 6 is disposed from the lower end portion on the center line in the concentration tank main body 21 to the upper end portion, and is disposed so as to be vertically rotatable at the center portion in the concentration tank main body 21.
The stirring device 6 includes a plurality of stirring blades 61 arranged in the vertical direction at the inner center of the concentration tank body 21, a stirring drive motor 62 that rotates the stirring blade 61, a rotating shaft 63 that fixes the stirring blade 61, A scraper 64 that rotates in the vicinity of the bottom portion 23 along the bottom portion 23, a conveying blade 65 disposed in the storage portion 26, a construction member 66 on which a stirring drive motor 62 is mounted, and the scraper 64 are fixed to the rotating shaft 63. The scraper support member 67 and a level control device 8 (see FIG. 1) for controlling the rotation of the stirring drive motor 62 are provided. The stirring blade 61, the scraper 64, the transport blade 65, and the rotating shaft 63 are integrally rotated by the stirring drive motor 62.

<Composition of stirring blade>
The stirring blade 61 is a blade member that stirs the concentrated slurry B in the inner bottom portion 23, and solid particles settle unevenly in the concentration tank body 21, or the concentrated slurry B has a high density (high concentration). In order not to become too much, it is raised (in the direction of arrows e and g) while being stirred to flow. The agitating blade 61 has a gap between four or three blades in a plan view in a spiral position at appropriate intervals in the vertical and horizontal directions on the rotating shaft 63 in the inner bottom portion 23. Is arranged through. In order to cause the slurry A to flow upward, the stirring blade 61 is provided on the rotating shaft 63, for example, inclined by 45 degrees with respect to the axial direction.

<Configuration of stirring drive motor>
As shown in FIG. 1, the stirring drive motor 62 is a drive source for rotating the rotating shaft 63, the stirring blade 61, the scraper 64, and the conveying blade 65 at a low speed (for example, about 1 to 6 rpm). The agitation drive motor 62 is mounted on the central part of the erection member 66 installed on the upper part of the concentration tank main body 21, and the upper end part of the rotating shaft 63 is connected thereto. The agitation drive motor 62 is a slurry that descends while rotating the rotary shaft 63 and the like inside the inner cylinder 5 in a spiral manner through a reduction mechanism (not shown) such as a gear reduction mechanism in response to a drive signal from the level control device 8. Rotate in the same direction (arrow c direction) as the spiral direction of A (arrow a direction). The stirring drive motor 62 is connected to the power source 10 via the level control device 8.

<Configuration of rotating shaft>
As shown in FIG. 2, the rotating shaft 63 is a rod-like member that is vertically arranged from the upper end portion to the lower end portion of the central portion in the concentration tank main body 21 and is rotated by the stirring drive motor 62. The rotating shaft 63 is arranged in a state where the upper end of the rotating shaft 63 hangs down by being connected to a stirring drive motor 62 arranged on the upper part of the concentration tank body 21 via a speed reduction mechanism (not shown), and the central portion is arranged in the inner cylinder 5 The lower end portion is disposed in the inner bottom portion 23 and the storage portion 26.

<Configuration of scraper>
As shown in FIG. 3, the scraper 64 is a member that scrapes solid particles deposited and deposited on the inner bottom 23 of the concentration tank body 21, and is fixed to the rotating shaft 63 with a scraper support member 67 interposed therebetween. Yes. The scraper 64 is composed of, for example, two members that are installed parallel (obliquely) along the inner bottom portion 23 with a predetermined interval (about 10 to 50 mm) above. The scraper 64 has an inner bottom scraping portion 64a provided along the inner bottom portion 23, and a body scraping portion 64b that is vertically connected to the upper side of the inner bottom scraping portion 64a in a side view. It is bent in a square shape.
The inner bottom scraping portion 64a is installed to be inclined at the same angle θ2 as the inclination angle θ1 of the inner bottom portion 23. The body scraping part 64b is arranged along the inside of the body part 22 of the concentration tank main body 21 with a predetermined interval.

<Construction of conveying wing>
The conveying blade 65 is a propeller for sending the concentrated slurry B in the storage unit 26 to the discharge port 24 formed on the inner wall of the storage unit 26, and is fixed to a rotating shaft 63 extending in the storage unit 26. Has been. The conveying blade 65 also serves as a component of the slurry discharge device 7.

<Configuration of scraper support member>
The scraper support member 67 is a member for fixing the scraper 64 to the rotating shaft 63, and includes an upper holding portion 67a, a middle holding portion 67b, and a lower holding portion 67c. The scraper support member 67 is formed, for example, by connecting metal pipes or square members by welding or fastening members.
The upper holding part 67a is a member for fixing the upper part of the scraper 64 to the rotating shaft 63, and is made of a rod-like member extending horizontally from the rotating shaft 63 in the outer peripheral direction.
The middle holding portion 67b is a rod-like member that connects and holds the central portion and the rotating shaft 63 to the scraper 64, and is disposed so as to be inclined downward from the connecting portion between the rotating shaft 63 and the upper holding portion 67a.
The lower holding portion 67 c is a portion that holds the lower end portion of the scraper 64 connected to the rotating shaft 63.

<Configuration of erection member>
As shown in FIG. 2, the erection member 66 is a substantially bridge-shaped member that is erected and arranged above the center of the opening of the concentration tank main body 21. On this erection member 66, a stirring drive motor 62 is mounted at the center, and a level sensor 71 is installed outside thereof. The erection member 66 is formed so that an operator can climb, and a safety handrail is provided around the erection member 66.

≪Configuration of slurry discharge device≫
As shown in FIG. 1, the slurry discharge device 7 is a device that sucks and removes the concentrated slurry B concentrated in the slurry concentration tank 2 from the slurry concentration tank 2, and includes the slurry concentration tank 2 and the dehydrator 9. Is intervening. The slurry discharge device 7 includes a level sensor 71 that measures the slurry level of the concentrated slurry B (solid particles) in the concentration tank body 21, and a slurry that is connected to the discharge port 24 on the upstream side and disposed on the dehydrator 9 on the downstream side. Solids in the concentrated slurry B detected by the transport pipe 73, the discharge pump 72 for flowing the concentrated slurry B in the concentration tank body 21 to the dehydrator 9 on the downstream side through the slurry transport pipe 73, and the level sensor 71. And a level control device 8 that drives and controls the discharge pump 72 based on the detection data of the pressure density of the particles.

<Configuration of level sensor>
The level sensor 71 is a sensor that detects the slurry level of the concentrated slurry B (solid particles) that has settled in the concentration tank body 21. The level sensor 71 is, for example, a cylinder 71a vertically disposed from the upper part in the concentration tank main body 21 to the lower end part in the body part 22, and the inside of the inner cylinder 5 and the body part 22 is settled to form a cylinder body. The electrode-type liquid level detection unit 71b that detects the liquid level of the supernatant liquid C above the solid particles of the concentrated slurry B that has entered the 71a, and the concentrated slurry B from the liquid level detected by the liquid level detection unit 71b. And a level control device 8 for calculating the pressure density.
That is, as shown in FIG. 2, the height H2 of the liquid level in the cylinder 71a is equal to the height H1 (see FIG. 3) of the concentrated slurry B collected so as to be deposited on the inner bottom 23 and the diluted slurry D. Is generated due to the difference between the pressure due to the height D2 (see FIG. 2) and the pressure due to the clarification liquid (not shown) such as industrial water supplied to the level sensor 71 from the outside. It becomes higher than the liquid level of C.
The liquid level detection unit 71b is a detection unit that detects the liquid level in the cylindrical body 71a. The liquid level detection unit 71b is arranged in the cylindrical body 71a so as to be graduated from the vertical direction at predetermined intervals to detect each liquid level. Consists of. In addition, each liquid level detection part 71b of the level sensor 71 is electrically connected to the level control device 8, and when the level control device 8 is ON, detection data is continuously sent.

<Exhaust pump configuration>
As shown in FIG. 1, the discharge pump 72 is an electric pump that is driven by a drive signal from the level control device 8 based on the slurry level of the concentrated slurry B in the concentration tank body 21 detected by the level sensor 71. The discharge pump 72 can adjust the concentration of the concentrated slurry B by sucking and extracting the concentrated slurry B settled on the inner bottom 23 from the inside of the concentration tank main body 21. The discharge pump 72 is electrically connected to the power supply 10 via the level control device 8.
The slurry transport pipe 73 is a pipe for sending the concentrated slurry B concentrated in the slurry concentration tank 2 to the dehydrator 9. The lower end portion of the downstream side of the slurry conveying pipe 73 is disposed on the filter cloth 91 of the dehydrator 9 and has a concentrated slurry supply port 73 a for discharging the concentrated slurry B onto the filter cloth 91.

≪Configuration of level controller≫
Based on the slurry level of the concentrated slurry B measured by the level sensor 71, the level control device 8 is configured so that the slurry level of the concentrated slurry B discharged from the discharge port 24 becomes a predetermined level set in advance. 3 is a level controller that drives and controls the supply pump 3 (not shown) and the discharge pump 72 to adjust the inflow amount of the slurry A and the extraction amount of the concentrated slurry B. The level control device 8 uses the liquid level detection signal transmitted from the liquid level detection unit 71b disposed at the liquid level in the cylindrical body 71a to determine the average of the diluted slurry D from the liquid level height H2. The slurry level (height) and pressure density are calculated, and the concentration of the concentrated slurry B discharged from the discharge port 24 is statistically calculated based on previously measured data.

≪Dehydrator configuration≫
As shown in FIG. 1, the dehydrator 9 is a device that dehydrates the moisture in the concentrated slurry B discharged from the slurry concentration tank 2 by the slurry discharge device 7. The dehydrator 9 is not particularly limited as long as it is a device that can further dehydrate the concentrated slurry B. Hereinafter, as an example of the dehydrator 9, the concentrated slurry B is poured onto the filter cloth 91, and the concentrated slurry B and the filter cloth 91 are squeezed with a pair of upper and lower squeezing rolls 93 and 94 to dehydrate them. The case will be described as an example.

  The dehydrator 9 is a filter cloth 91 poured into the concentrated slurry B and formed into a conveyor belt shape, a transport roll 92 for moving the filter cloth 91, and the concentrated slurry B transported by the filter cloth 91. Squeezing rolls 93 and 94 for removing moisture by squeezing, a scraper 95a for a dehydrator for scraping off the dewatered cake E dehydrated by the squeezing roll 93 and transferred to the squeezing roll 93, and for the dehydrator A chute 95b for transporting the dewatered cake E scraped off by the scraper 95a to a predetermined position, a washing nozzle 97 for washing the filter cloth 91 with washing water, and a water receiving chute for receiving the washing water dropped from the filter cloth 91 96 and dewatering rolls 98 and 98 for squeezing and removing the moisture of the filter cloth 91 containing the washing water. The dehydrator 9 is electrically connected to the level control device 8 and is driven and stopped by a detection signal from the level sensor 71 and a manual switch (not shown).

<Composition of filter cloth>
The filter cloth 91 is a conveyor belt made of felt woven of fibers or untwisted cloth and having good moisture absorption. The filter cloth 91 is moved at a steady speed by the transport roll 92 and transports the concentrated slurry B placed on the filter cloth 91 to the squeezing rolls 93 and 94 and the washing nozzle 97 until the original concentrated slurry supply port 73a is reached. Move constantly at a predetermined speed.

<Configuration of transport roll and pressing roll>
The transport roll 92 is a roll for moving the wound filter cloth 91 to a predetermined position, and includes a plurality of rolls installed at appropriate positions, and can adjust the slack and tension of the belt-covered filter cloth 91. It is like that.
The squeezing rolls 93 and 94 are composed of a pair of rolls that are arranged above and below the filter cloth 91 and rotate at a predetermined speed, and the filter cloth 91 is wound around one of the squeezing rolls 94. One squeezing roll 94 and the other squeezing roll 93 squeeze the filter cloth 91 and the concentrated slurry B to squeeze out the water in the concentrated slurry B. The squeezing roll 94 is driven by a motor (not shown) and runs a filter cloth 91 belted.

<Configuration of scraper for dehydrator and water receiving chute>
The dewatering machine scraper 95 a is a device that scrapes off the dewatered cake E obtained by transferring the dehydrated cake E in a cake state to the upper pressing roll 93 by the pressing rolls 93 and 94. The dewatered cake E scraped off by the dewatering machine scraper 95a is transported to a predetermined position by the chute 95b and collected.
As shown in FIG. 1, the water receiving chute 96 is for recovering the cleaning liquid and the dehydrating liquid for cleaning the filter cloth 91.

<Configuration of cleaning nozzle and dewatering roll>
The cleaning nozzle 97 is a cleaning device that cleans the filter cloth 91, and includes a pair of nozzles that spray and spray cleaning water on the filter cloth 91. The cleaning nozzle 97 is composed of a pair of nozzles for cleaning the front and back of the filter cloth 91 that is lifted upward from the water receiving chute 96 and conveyed. The sprayed nozzle cleaning water falls and is collected in the water receiving chute 96.
The dewatering rolls 98 and 98 include a pair of rolls for removing water such as washing water in the filter cloth 91, the filter cloth 91 is wound around one dewatering roll 98, and the filter cloth is filtered by the other dewatering roll 98. The water in the filter cloth 91 is squeezed out by squeezing 91 and one roll. The dewatering roll 98 moves the filter cloth 91 from which moisture has been removed to the lower side of the original concentrated slurry supply port 73a.

≪Operation of slurry processing equipment≫
Next, the operation of the slurry processing apparatus 1 will be described with reference to FIGS.
As shown in FIG. 5, first, when the power supply 10 and the level control device 8 are turned on (step S1), the slurry level in the slurry concentration tank 2 is measured by the level sensor 71 (step S2).
In the agglomeration reaction tank 3, the slurry A in the liquid state is supplied from the slurry inlet 32 into the agglomeration reaction tank 3 by a supply pump (not shown) for slurry A, and the polymer flocculant F is fed from the flocculant inlet 33 to the polymer. It is supplied into the agglomeration reaction tank 3 by a supply pump (not shown) for the aggregating agent F (step S4). When the agglomeration reaction tank agitation motor 36 is driven to rotate, the agglomeration reaction tank scraper 35 is rotated and the slurry A in the agglomeration reaction tank 3 is agitated. In this case, the agglomerated aggregate is uniformly mixed with the high specific gravity powder and the low specific gravity powder, and there is no specific gravity difference between the aggregates. It becomes possible to obtain the concentrated slurry B that settles in

  When the slurry A in the agglomeration reaction tank 3 exceeds the height of the slurry outlet 37, the slurry A in the agglomeration reaction tank 3 flows into the slurry outlet 37 and is supplied from the slurry supply path 4 to the upper part of the inner cylinder 5. . The open end 41a of the slurry supply path 4 is connected to be shifted from the center position of the inner cylinder 5 (see FIG. 4). Therefore, as shown in FIG. 2, the slurry A descends while being guided by the inner wall of the inner cylinder 5 while winding a spiral vortex downward in the inner cylinder 5.

Slurry A coming out from the lower opening end of the inner cylinder 5 flows downward (in the direction of arrow a) with the momentum of the flow in the inner cylinder 5, and the rotation of the stirring blade 61 disposed below the inner cylinder 5. Is stirred in the concentration tank body 21 to make the concentration uniform. Then, the solid particles in the slurry A settle down toward the lower side due to their own weight to generate a concentrated slurry B that is uniformly concentrated.
In this case, the solid particles in the concentrated slurry B that have settled on the inner bottom portion 23 slide down the slope (direction of arrow d) because the inner bottom portion 23 is formed on a steep slope. Even if the solid particles are deposited on the inner bottom 23, the vicinity of the inner bottom 23 is scraped off by the scraper 64 rotating along the inner bottom 23, and slides downward (arrow d).
Part of the solid particles in the concentrated slurry B descending the inner bottom portion 23 flows into the lowermost storage portion 26 of the concentration tank body 21, and the other solid particles are in the lower layer in the inner bottom portion 23 due to the rotation of the stirring blade 61. From the inside (in the direction of arrow e), and circulates (in the direction of arrows e, f, and d) and flows with little accumulation on the inner bottom 23.

The dilute slurry D and the supernatant C, which have a lighter specific gravity than the concentrated slurry B, are separated from the concentrated slurry B and moved upward (arrow b direction) while swirling by the upward flow (arrow g direction) by the stirring blade 61. The dilute layer D1 in which the dilute slurry D gathers is formed on the upper side of the concentrated layer B1 below the concentrating tank body 21.
Further, the slurry A (solid particles) in the dilute layer D1 is separated into solid and liquid, and rises upward (in the direction of arrow b) while flowing in a vortex to produce a purified supernatant C, which is diluted. A supernatant layer C1 is formed on the layer D1.

  The supernatant C is separated from the turbid liquid slurry A and flows into the upper layer side in the concentration tank body 21 in a state containing the eluted salts. As the water level increases, Then, it passes over the weir 27 and falls into the supernatant liquid recovery path 28. The supernatant C flowing into the supernatant recovery path 28 is drained out of the slurry concentration tank 2 from the overflow part 25. In addition, the supernatant liquid C discharged | emitted from the overflow part 25 is sent to a process tank (illustration omitted) as a process liquid which removed the heavy metal, and is processed or stored.

The concentrated slurry B that has flowed in the vicinity of the reservoir 26 is sucked by the transport blade 65 and sent to the slurry transport pipe 73 outside the concentrate tank body 21 through the reservoir 26 and the discharge port 24. In this case, in the inner bottom 23, the stirring slurry 61, the scraper 64, and the conveying blade 65 are rotating, so that the concentrated slurry B is constantly flowing, so a so-called rat hole of solid particles is formed. There is nothing. For this reason, it can be solved that solid particles are deposited and solidified on the inner bottom portion 23 and the storage portion 26, and a path for the dilute slurry D to flow out from the discharge port 24 is formed.
In the present invention, solid particles can be prevented from accumulating by the steep slope of the inner bottom 23 and the stirring device 6, and can always be made to circulate in the concentration tank body 21.

As shown in FIG. 1, the slurry level of the solid particles settled in the concentration tank body 21 is measured by the level sensor 71, and the measurement data is continuously sent to the level control device 8 (step S3).
When the slurry level of the concentrated slurry B measured by the level sensor 71 is less than the predetermined level set in the level control device 8 in advance, the level control device 8 turns off the discharge pump 72 provided in the slurry transport pipe 73. While maintaining the ON state of the supply pump (not shown) for the slurry A in the aggregation reaction tank 3 and the supply pump (not shown) for the polymer flocculant F, the slurry A is continuously added to the slurry concentration tank 2. (Yes in step S4).

  When the slurry level of the concentrated slurry B measured by the level sensor 71 is equal to or higher than a predetermined level (No in step S4), the level control device 8 causes the concentrated slurry B in the concentration tank body 21 to have a predetermined level concentration. The exhaust pump 72 and the dehydrator 9 are driven (step S5). By driving the discharge pump 72, the concentrated slurry B in the reservoir 26 is discharged by the weight of the concentrated slurry B and the like and the suction force of the discharge pump 72, and passes through the slurry transport pipe 73 and from the concentrated slurry supply port 73a. Nine filter cloths 91 are supplied.

  The concentrated slurry B dropped on the filter cloth 91 is squeezed and dehydrated by the squeezing rolls 93 and 94 together with the filter cloth 91 by the rotation drive of the transport roll 92. The dewatered concentrated slurry B becomes a flaky dewatered cake E, and is scraped off by the dewatering machine scraper 95a. Thus, the slurry processing apparatus 1 can obtain a system capable of concentrating the slurry A to a high concentration by combining the slurry concentrating tank 2 and the dehydrator 9, and the capacity of the dehydrator 9 can be increased. Be improved. The dewatered cake E becomes flakes, becomes moisture and shape optimal for recycling, and is transferred to a predetermined storage location by the chute 95b.

The filter cloth 91 from which the dewatered cake E has been scraped is moved by the transport roll 92 and the solid particles adhering to the water receiving chute 96 are dropped. Further, the filter cloth 91 is washed away by washing water being sprayed from the washing nozzle 97. For this reason, the water in the water receiving chute 96 becomes a turbid liquid in which solid particles are mixed. This turbid liquid is collected and processed in a predetermined place.
The filter cloth 91 containing the washing water from the washing nozzle 97 is squeezed out by the dewatering roll 98, so that the concentrated slurry B in which the moisture of the filter cloth 91 is supplied onto the filter cloth 91 from the concentrated slurry supply port 73a. Is not absorbed by

When the slurry slurry in the slurry concentration tank 2 is extracted by the slurry discharging device 7 and the slurry level of the concentrated slurry B decreases to a concentration lower than a predetermined level (Yes in step S6), the level sensor 71 detects it. The measurement data is detected and transmitted to the level control device 8. The level control device 8 determines that the slurry level of the concentrated slurry B has decreased to a concentration equal to or lower than the predetermined level, and immediately stops the discharge pump 72 and the dehydrator 9 (step S7).
In addition, when the slurry level of the concentrated slurry B does not fall below a predetermined level, the driving state of the slurry discharge device 7 and the dehydrator 9 is maintained (No in step S6). And if the power supply 10 is turned OFF, the slurry processing apparatus 1 will stop (step S8).

  As described above, the present invention improves the dewatering capability of the dehydrator 9 by sending the concentrated slurry B concentrated at a high concentration in the slurry concentration tank 2 to the dehydrator 9 by the slurry discharge device 7 and dehydrating it. Furthermore, a low-moisture flaky dehydrated cake E can be obtained.

  The present invention is not limited to the above-described embodiment, and various modifications and changes can be made within the scope of the technical idea. The present invention extends to these modifications and changes. Of course.

For example, although the case where the slurry A containing solid particles of incinerated fly ash was concentrated was described as an example, a turbid liquid in which solid particles such as ceramics, sludge, and debris are suspended in the liquid It can also be applied to the case of concentrating.
The dehydrator 9 may be other types such as a vacuum drum dehydrator or a centrifugal dehydrator. Further, the propeller-shaped stirring blade 61 may be any one that allows the concentrated slurry B to flow upward, and may be, for example, a screw.
Further, the level sensor 71 may be any sensor that can measure the concentration of the concentrated slurry B, and may be another sensor such as an ultrasonic level sensor, for example.

  The inclination angle θ1 of the inner bottom 23 of the concentration tank main body 21 is not limited as long as solid particles can easily flow downward on the inner bottom 23, and the bottom surface of the inner bottom 23 has wear resistance and lubricity. By providing an excellent ultra high polymer resin film or a low friction sheet, a gentle inclination angle may be used.

DESCRIPTION OF SYMBOLS 1 Slurry processing apparatus 2 Slurry concentration tank 3 Concentration tank main body 4 Slurry supply path 5 Inner cylinder 6 Stirrer 7 Slurry discharge apparatus 8 Level control apparatus 9 Dehydrator 21 Concentration tank main body 22 Body part 23 Inner bottom part 24 Outlet 25 Overflow part 26 Reservoir 61 Agitating blade 62 Agitating drive motor 63 Rotating shaft 64 Scraper 65 Conveying blade 71 Level sensor 72 Discharge pump 73 Slurry conveying tube A Slurry B Concentrated slurry C Dilute slurry E Dehydrated cake θ1 Tilt angle

Claims (6)

In a slurry processing apparatus equipped with a slurry concentration tank that separates solid particles in the slurry into a concentrated slurry obtained by concentrating the slurry and a supernatant liquid,
A substantially funnel-shaped concentrating tank having a discharge port for discharging the concentrated slurry at the inner bottom, a cylindrical body part for storing the supernatant liquid at the upper part, and an overflow part for discharging the supernatant liquid The body,
A slurry supply path for supplying the slurry into the concentration tank body;
A stirring device rotatably disposed inside the concentration tank body,
The stirring device includes a plurality of stirring blades for flowing upward the concentrated slurry that has settled from above in the concentration tank body;
A rotating shaft provided with the plurality of stirring blades;
A slurry processing apparatus, comprising: an agitation drive motor that rotates the rotating shaft.   2. The inner bottom portion is formed in an inverted conical shape having an inclination angle in which the solid particles sinking on the inner bottom portion flow downward on the inner bottom portion. The slurry processing apparatus according to 1.   The stirring device is disposed above the inner bottom portion of the concentrating tank main body at a predetermined interval, and is fixed to the rotating shaft, and the stirring drive motor rotates to settle on the inner bottom portion. The slurry processing apparatus according to claim 1, further comprising a scraper that scrapes off the concentrated slurry. The inner bottom part has a storage part provided with the discharge port at the lowermost part of the center part,
The storage portion is provided with a conveying blade fixed to a lower end portion of the rotating shaft, rotating in the same direction as the scraper, and sending the concentrated slurry in the storage portion to the discharge port. The slurry processing apparatus of any one of Claim 1 thru | or 3. In the concentration tank body, a level sensor that detects a slurry level of the concentrated slurry that has settled on the inner bottom,
A discharge pump for sucking the concentrated slurry in the reservoir and sending it to the downstream side is installed, and a slurry transport pipe communicating with the discharge port is provided.
The slurry processing apparatus according to claim 4, wherein the discharge pump is rotated by a drive signal based on a slurry level of the concentrated slurry detected by the level sensor. The slurry processing apparatus according to claim 5, wherein the concentrated slurry sent to the downstream side of the slurry transport pipe by the discharge pump is dehydrated by a dehydrator that dehydrates moisture in the concentrated slurry. .

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