JP2009022873A - Sludge agglomeration mixing equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sludge flocculating/mixing device where the tangling of a fibrous material in sludge to a stirrer can be prevented, and a maintenance operation is facilitated as well. <P>SOLUTION: In the sludge flocculating/mixing device 1 where sludge and a flocculant fed into a tank 2 are mixedly stirred by a stirrer 10, and is made to flow out from a flocculated sludge discharge port 5, the stirrer 10 is composed in such a manner that a plurality of stirring rods 12 are radiatedly and downwardly tilted to the lower part of a rotary shaft 11 elongating to the upper part from a position separated from the liquid face of the liquid in the tank body 2 to the upper side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sludge aggregating apparatus that generates agglomerated sludge by mixing and stirring sludge and a flocculant (including a case where a coagulant auxiliary is added).

Conventionally, as an agglomerating and mixing apparatus for producing agglomerated sludge by mixing and stirring sludge and a flocculant, a stirrer in which a paddle type agitating blade (agitating blade) is attached to a rotating shaft vertically installed in a tank body is provided. There are a thing (for example, refer to patent documents 2) and a thing (for example, refer to patent documents 2) which provided a stirrer which attached a propeller type (it is also called a screw type) stirring blade to the above-mentioned axis of rotation.
JP 62-197110 A JP 2000-317214 A

  However, when the sludge agglomeration and mixing device described in Patent Documents 1 and 2 is used as a sewage sludge agglomeration and mixing device, fibers such as hair that are abundantly contained in the sludge are entangled with paddle-type or propeller-type stirring blades, and sludge The above-mentioned fibers are also entangled in the rotating shaft that rotates in a dipped state, and these entangled fibers grow in a lump to reduce the stirring action, and these entangled fibers are frequently removed manually. Therefore, there is a problem that it takes time and effort for maintenance.

  Therefore, as shown in FIG. 3, as shown in FIG. 3, a small flat plate-shaped stirring blade 34 that extends substantially along the entire length of the rotating shaft 33 is provided on the rotating shaft 33 that is provided vertically in the tank body 32, to prevent the above-described fiber entanglement. There is also an example in which a sludge agglomeration and mixing device 31 is used in which a long vane type stirrer 35 attached in a radial pattern is rotationally driven by a driving device 36 having a motor as a prime mover. In addition, illustration of the supply port of sludge and a flocculant, the discharge port of agglomerated sludge, etc. is abbreviate | omitted in the figure.

  However, in the sludge aggregation and mixing device 31 described above, the entanglement of the fibers on the stirring blade 34 and the rotary shaft 33 is reduced. To prevent this entanglement, the stirring blade 34 formed of a small flat plate has a stirring ability. In order to ensure, it is necessary to make it the long stirring blade 34 which reaches the bottom part of the tank body 32 as shown in the figure, and it becomes difficult to support the cantilever only at the upper part of the rotating shaft 33, and the lower end part of the rotating shaft 33 is used as the tank. It is necessary to provide a lower bearing 37 that is rotatably supported in the body 32. For this reason, at the time of periodic inspection of the lower bearing 37, it is necessary to discharge the entire amount of sludge in the tank body 32 and to perform inspection work in the tank body 32, and there is a problem that maintenance work is extremely complicated. Met.

  An object of the present invention is to provide a sludge agglomeration and mixing device that prevents the fiber stirrer in sludge from being entangled with the stirrer and facilitates maintenance work.

  In order to achieve the above object, the sludge agglomeration and mixing apparatus of the present invention is the sludge agglomeration and mixing apparatus in which the sludge and the flocculant supplied into the tank are mixed and agitated by a stirrer to flow out from the agglomerated sludge discharge port. The stirrer is characterized in that a plurality of stirring rods are attached to a lower part of a rotating shaft extending upward from a position spaced above the liquid level of the fluid in the tank body, and are inclined radially and downward. .

  When configured in this manner, during mixing and stirring of the sludge and the flocculant by rotating the stirrer, the fiber in the sludge is entangled with the rotating shaft portion located above the liquid level of the fluid in the tank body. In addition, even when the fiber is caught by the rotating stirring rod, the stirring rod is inclined radially and downward, so that the fiber is driven obliquely downward along the stirring rod by centrifugal force and stirred. The fiber is not separated from the tip of the rod, and the fiber is not entangled with the stirring rod and coarsened into a lump. And by preventing this fiber entanglement, it is no longer necessary to clean the stirrer over a long period of time, and at the bottom of the tank, there is no need for a lower bearing for supporting the rotating shaft, so that complicated inspection work is unnecessary, Maintenance work is extremely easy.

  As described above, according to the present invention, entanglement of the fibrous stirrer in the sludge is prevented and maintenance work is facilitated.

  Hereinafter, an embodiment of the present invention will be described with reference to an example shown in FIGS. In the figure, 1 is a sludge agglomeration and mixing device for agglomeration and mixing of sewage sludge, 2 is a tank body for receiving sludge and aggregating agent (including the case where a coagulant aid is added), and the cover plate 2a has a sludge A supply port 3 and a flocculant supply port 4 are provided, and an agglomerated sludge discharge port 5 is provided at the upper part of the side wall.

  10 is a stirrer that is provided at the center of the tank body 2 and mixes and stirs the sludge and the flocculant in the tank body 2, and is a liquid 6 fluid that is a mixture of sludge, flocculant, water, and the like in the tank body 2. The three round steel stirring rods 12 are inclined radially and downward as shown in FIG. 2 to the lower large diameter portion 11a of the rotating shaft 11 extending upward from a position spaced above the surface 7, It is fixedly attached by welding. In addition, the inclination angle (relative to the horizontal plane) of the stirring rod 12 in this example is 60 degrees.

  The rotating shaft 11 passes through a seal portion 21 provided on the cover plate 2 a and is rotatably supported by a bearing 22. An upper end portion of the rotating shaft 11 is connected to an output shaft 25 a of a driving device 25 including a motor 23 and a speed reducer 24. It is connected.

  In the sludge coagulation / mixing apparatus 1 having the above-described configuration, the sludge is supplied from the sludge supply port 3 and the coagulant is supplied from the coagulant supply port 4 to the tank body 2, and the stirrer 10 is rotationally driven by the driving device 25. The sludge and the flocculant are mixed and agitated, and the sludge generated thereby flows out in the form of overflowing the sludge discharge port 5, is supplied to the subsequent dewatering device, etc., and the liquid 6 in the tank 2 is liquidized. Surface 7 is maintained at a substantially constant level.

  During this mixing and stirring, the stirrer 10 that is driven to rotate around the vertical axis is located at a position above the liquid surface 7 so that the fiber in the sludge is not entangled with the rotating shaft 11 at all. If the fiber is caught by the rotating stirring rod 12 and tries to get entangled, the stirring rod 12 is inclined radially and downward, so that the fiber is inclined along the stirring rod 12 by the centrifugal force due to the rotation. Driven downward, disengages from the tip of the stirrer 12, and the fiber is entangled with the stirrer 12 and grows into a lump so that the stirring ability is not reduced and the required rotational driving force is not increased. Stable mixing and stirring can be performed over time.

  And since the entanglement of the fiber is prevented in this way, it is not necessary to perform the cleaning operation of the stirrer 10 for removing the fiber over a long period of time, and in the conventional sludge agglomeration and mixing apparatus 31 shown in FIG. Since such a lower bearing 37 at the bottom of the tank body is not necessary, no complicated inspection work for the lower bearing 37 is required, and the maintenance work becomes extremely easy.

  In addition, the quality and amount of sludge supplied from the sludge supply port 3 can be selected by selecting the length of the stirring rod 12, the angle of inclination, the length of the stirring rod according to the internal dimensions of the tank body 2, the selection of the rotational drive speed, and the like. Corresponding and appropriate sludge coagulation mixing ability can be obtained.

  The present invention is not limited to the above example. For example, the material and cross-sectional shape of the stirring rod 12, the mounting method to the rotating shaft 11, the number and inclination angles of the above-mentioned (stirring rod), the shape of the rotating shaft 11, The specific configuration of each part such as the rotation support structure and the type of the driving device 25 may be other than the above. Further, the stirring bar 12 may be a curved stirring bar in addition to the straight stirring bar in the above example.

  In addition to sewage sludge, the present invention can also be applied to sludge coagulation and mixing devices such as human waste sludge, clean water sludge, industrial wastewater sludge, etc. The present invention can also be applied to a sludge coagulation and mixing device in which a large number of spheres having a specific gravity are mixed.

  In addition to the sludge agglomeration and mixing device that supplies the agglomerated sludge generated by mixing and stirring sludge to the dehydration process, the present invention mixes and agitates sludge and an inorganic flocculant according to the sludge properties to obtain primary agglomerated sludge. The present invention can be applied to both primary and secondary agglomeration mixing devices when an amphoteric polymer flocculant is added and mixed and stirred to obtain a secondary agglomerated sludge (granulated sludge). And when both tanks of this primary and secondary coagulation mixer are adjacent, or when the tank body of sludge coagulation mixer is adjacent to the subsequent sedimentation tank, etc. The overflow overflow weir can be used as an aggregate sludge discharge port.

It is a longitudinal cross-sectional view of the sludge coagulation | mixing apparatus which shows an example of embodiment of this invention. It is the sectional view on the AA line of FIG. It is a schematic longitudinal cross-sectional view which shows an example of the conventional sludge aggregation and mixing apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Sludge aggregation mixing apparatus, 2 ... Tank body, 3 ... Sludge supply port, 4 ... Coagulant supply port, 5 ... Aggregation sludge discharge port, 6 ... Fluid, 7 ... Liquid level, 10 ... Stirrer, 11 ... Rotating shaft , 12 ... stirring rod, 22 ... bearing, 25 ... drive device.

Claims (1)

In the sludge flocculation and mixing device that mixes and stirs the sludge and flocculant supplied into the tank with a stirrer and flows out of the sludge discharge port,
The stirrer is formed by attaching a plurality of stirring rods radially and downwardly to a lower part of a rotating shaft extending upward from a position spaced above the liquid level of the fluid in the tank. Sludge aggregation and mixing equipment.

Images