JP3358535B2 - Coagulation settling equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses plant wastewater, well water, river water, lake water and the like as a stock solution, and adds a flocculant to the stock solution to precipitate and separate suspended substances contained in the solution. The present invention relates to a coagulation sedimentation treatment device.

[0002]

2. Description of the Related Art A conventional coagulation and sedimentation tank has a structure in which a stirring tank for charging and stirring a coagulant, a coagulation tank for forming flocs, and a sedimentation tank for sedimenting flocs are separated. For this reason, there is a problem that the entire apparatus becomes large. This is because, when the stirring tank, the flocculation tank and the sedimentation tank are integrally formed, the flow in the sedimentation tank located downstream of the stirring tank is disturbed by the stirring in the stirring tank. This is because it is not performed.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a compact coagulation / sedimentation treatment apparatus in view of the above problems.

[0004]

Means for Solving the Problems The present invention has been made to solve the above problems, and the invention according to claim 1 has a first stirring section for adding a flocculant to a stock solution. A second stirring unit for forming flocs, a sedimentation unit for sedimenting flocs, and a second stirring unit 3
The plurality of communication holes 12, 12,...
The formed second stirring section 3 and the settling section 4 are partitioned.
Straightening wall 11 and a front of the straightening wall 11 of the straightening wall 11
The collision plate 20 provided for each communication hole 12 is
And characterized by comprising also the invention of claim 2, partition and said second stirring portion and the first agitating part with the partition wall
An inclined plate is provided in the settling portion , and the invention according to claim 3 is characterized in that the inclined plate is provided in parallel with the liquid flow.

[0005]

Next, an embodiment of the present invention will be described. This invention provides a coagulating sedimentation processing apparatus comprising a first agitating part for adding a flocculant to the stock solution, the second stirring unit for forming a floc, a precipitation unit for precipitating flocs, the second Stirrer 3 and settling unit
And a plurality of communication holes 12, 12,.
In addition, rectification for partitioning the second stirring section 3 and the precipitation section 4
A wall 11 and the respective connecting portions are provided on a side of the
A collision plate provided for each of the through holes;
This is achieved by: The first stirrer is provided with a first stirrer and a flocculant charging device, and the second stirrer is provided with a second stirrer. And the said 1st stirring part and the said 2nd stirring part are divided by the partition comprised from a 1st partition and a 2nd partition.

[0006] The second stirring section and the settling section are defined by a flow regulating wall having a plurality of communication holes communicating the second stirring section and the settling section. Also,
On the settling portion side of the flow regulating wall, a collision plate is provided for each of the communication holes at a predetermined distance from the flow regulating wall. Further, an inclined plate is provided in the settling section.

Next, a method of coagulation and sedimentation in the above-described configuration will be described. First, the stock solution flows into the first stirring section, where it is strongly stirred together with the coagulant added from the coagulant charging device. Thereafter, the liquid passes between the first partition and the second partition and flows into the second stirring unit. In the second stirring section, the stirring is performed more slowly than in the first stirring section. As a result, the suspended matter in the liquid forms flocs.

[0008] Then, the liquid containing the flocs passes through the communication hole formed in the flow regulating wall at a high speed and collides with the collision plate.
As a result, due to the action of the collision plate, the momentum of the flow of the liquid containing the flocs is attenuated, and the flow velocity is sufficiently reduced. Thus, by providing the collision plate, flocs can be effectively settled in the sedimentation section on the downstream side, and the entire apparatus can be made compact.

As described above, the liquid having a sufficiently low flow rate passes through the inclined plate portion of the settling section. Here, the flocs in the liquid settle down toward the bottom of the settling section by the action of gravity while moving in a direction parallel to the inclined plate. After colliding with the inclined plate, it rolls down toward the bottom along the inclined plate. At this time, the flocks that have collided with the inclined plate move together while colliding with each other, and with this movement, flocs having a higher specific gravity are gradually formed in a snowball manner, so that the sedimentation speed of the flocs is increased. Thus, the action of the inclined plate promotes the sedimentation speed of the floc to about 10 times as compared with the case without the inclined plate. Therefore,
The liquid containing flocs can be efficiently separated into flocks and clean liquids.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. 1 and 2 showing an embodiment of the present invention will be described. FIG. 1 is an explanatory plan view schematically showing the entire coagulation / sedimentation treatment apparatus according to the present invention.
FIG. 2 is an explanatory side view schematically showing the entire coagulation / sedimentation treatment apparatus according to the present invention.

In FIG. 1 and FIG. 2, a coagulation / sedimentation treatment apparatus 1 includes a first stirring section 2 for adding a coagulant to a stock solution.
And a second stirring section 3 for forming flocs, a settling section 4 for precipitating flocs, and a liquid sending tank section 5 for temporarily storing a liquid from which flocs have been removed. The first stirring unit 2 includes the first stirring unit 2.
A first stirrer 6 for stirring the inside is provided, and a flocculant charging device 7 for adding a flocculant to the stock solution in the first stirring section 2 is provided.

The second stirring section 3 is provided with a second stirrer 8 for stirring the inside of the second stirring section 3 to form flocs. The stirring by the second stirrer 8 is performed at a slower rotation speed than the stirring by the first stirrer 6 in order to form flocs efficiently.

The first stirring section 2 and the second stirring section 3 are partitioned by a partition composed of a first partition 9 and a second partition 10. Even if the first partition 9 and the second partition 10 are strongly stirred by the first stirrer 6 in the first stirrer 2, the stirring is performed by the second stirrer 3 and the second stirrer 3 on the downstream side. This is for preventing the influence of the flow on the settling section 4. When the first partition 9 and the second partition 10 having the shapes shown in FIG. 1 are provided, when the stirring by the first stirrer 6 is performed in the clockwise rotation direction when viewed from above the plane, the liquid Pass through the space between the first partition 9 and the second partition 10 from the first stirring unit 2 and do not immediately flow toward the second stirring unit. Therefore, the first stirring unit 2
Is preferably performed because the stirring is sufficiently performed.

The second stirring section 3 and the precipitation section 4
Are defined by the rectifying wall 11 and communicate with each other by a plurality of communication holes 12, 12,... Formed in the rectifying wall 11. In addition, the second stirring unit 3 and the rectifying wall 1
1, a shielding wall 13 is provided. The shielding wall 13 prevents disturbance of the liquid flow in the sedimentation section 4 on the downstream side caused by stirring of the second stirrer 8.

The settling section 4 is provided with a plurality of inclined plates 14, 14,... For effectively settling the flocs formed in the second stirring section 3.
The shape of the bottom of the settling portion 4 is tapered in order to easily discharge the settled flocs. A discharge line 15 for discharging the floc settled in the sedimentation section 4 is connected to the bottom of the sedimentation section 4. The discharge line 15 is provided with a discharge valve 16.

Further, the settling section 4 and the liquid sending tank section 5
Is partitioned by the overflow weir 17. This overflow weir 17
Is provided slightly inclined from the vertical direction toward the liquid sending tank unit 5 side. Due to this inclination, a flow is generated from the bottom of the sedimentation section 4 to the upper end of the overflow weir 17 to regulate the entire flow in the sedimentation section 4 and secure a larger volume of the sedimentation section 4. be able to.

Further, an undiluted solution supply pipe 1 for supplying undiluted solution to the first agitating unit 2 is provided above the first agitating unit 2.
8 are connected. A processing liquid pipe 19 for supplying a processing liquid to the outside of the apparatus is provided at the bottom of the liquid sending tank section 5.
Is connected.

Here, the rectifying wall 11 and the collision plate 20
Will be described in detail with reference to FIG. FIG.
FIG. 3 is an enlarged cross-sectional explanatory view taken along line III-III of FIG. 3, and is an enlarged cross-sectional explanatory view showing a portion of the rectifying wall 11 and the collision plate 20 in detail. As described above, the communication hole 12 having a hole diameter of about 10 mm is formed in the flow regulating wall 11.
Are arranged in a grid pattern. The number of these communication holes 12 is appropriately determined according to the flow rate of the processing liquid. In addition, a plurality of collision plates 20, 2 are provided on the flow regulating wall 11.
Are fixed by the collision plate fixing members 21, 21,... So that 0,. The shape of each of these collision plates 20 is
The shape is not limited to a square as shown in FIG. 3, but may be a circle, for example. Each of the collision plates 20 is provided at a position separated from the rectifying wall 11 by at least twice the diameter of each of the communication holes 12, and a large rectifying effect can be obtained even with a short interval of, for example, 20 mm.

Next, with respect to each of the inclined plates 14, FIG.
This will be described in detail with reference to FIG. FIG. 4 is a cross-sectional explanatory view taken along the line IV-IV in FIG. 1, and is a cross-sectional explanatory view showing a portion of each of the inclined plates 14 in detail. In the coagulation sedimentation treatment apparatus 1, the liquid flow passes from the rectifying wall 11 to the sedimentation part 4 and reaches the overflow weir 17, but each of the inclined plates 14
It is provided so as to be parallel to this liquid flow. A plurality of the inclined plates 14 are provided with a predetermined gap, and the gap is preferably 50 to 100 mm. According to experiments performed by the inventors, the angle of inclination of each of the inclined plates 14 is preferably 45 ° to 60 °. When the angle of inclination is 60 °, the sedimentation speed of the floc is the fastest, which is preferable. is there.

By the way, the flocs that roll down and settle on the inclined plates 14 reach the lowermost ends of the respective inclined plates 14 and then sink toward the bottom. In order to prevent the liquid from flowing out of the sedimentation section 4 along with the liquid flow in the portion where each of the inclined plates 14 does not exist, a weir plate 22
Is provided.

Next, the coagulation-sedimentation process in the configuration of the above embodiment will be described. First, the stock solution flows into the first stirring unit 2 via the stock solution supply pipe 18. A coagulant is added to the inflowing stock solution from the coagulant charging device 7 and the inside of the first stirring unit 2 is strongly stirred by the first stirrer 6. After this stirring, the liquid passes between the first partition 9 and the second partition 10 and flows into the second stirring unit 3.

Then, in the second stirring section 3, due to the gentle stirring of the second stirrer 8, the suspended substance in the liquid forms flocs by the action of the coagulant.

Then, the liquid containing the floc is supplied to the rectifying wall 1.
After passing through each of the communication holes 12, it collides with each of the collision plates 20. The flow rate of the liquid in each of these communication holes 12 is 100
Although the speed is higher than 0 m / h, the momentum of the liquid is attenuated by the action of each of the collision plates 20, and the flow velocity is reduced to about 5 m / h. Thus, even if the distance between the flow regulating wall 11 and each of the collision plates 20 is a very short distance of about 100 mm, the flow velocity of the liquid can be sufficiently reduced,
Accordingly, flocs can be effectively settled in the sedimentation section 4 on the downstream side, and the entire apparatus can be made compact.

As described above, the liquid having a sufficiently low flow rate passes through each of the inclined plates 14 of the settling section 4. Here, the flocs in the liquid settle down in the direction of the bottom of the sedimentation section 4 by the action of gravity while moving in a direction parallel to each of the inclined plates 14. Then, after colliding with each of the inclined plates 14, it rolls down toward the bottom along each of the inclined plates 14. At this time, the flocs that collided with the respective inclined plates 14 move together while colliding, and with this movement, gradually form a floc with a specific gravity in the form of a snowman, so that the sedimentation speed of the flocs is high. Become. Then, the floc that has reached the lowermost end of each of the inclined plates 14 falls on a portion without each of the inclined plates 14 and accumulates on the bottom. Thus, 50-100
By the action of the inclined plates 14 provided at intervals of mm, the sedimentation speed of the flocs is promoted to about 10 times as compared with the case where the inclined plates 14 are not provided. Therefore, the liquid containing flocs can be efficiently separated into flocs and clean liquids.

In the case where the inclined plates 14 are not provided, a considerable distance in the flow direction of the liquid is required in order to sufficiently settle the flocs in the liquid to obtain a clean liquid. Therefore, the size of the apparatus is increased accordingly. At this point, each of the inclined plates 14
It is very effective in reducing the size of the device.

The liquid cleaned in the sedimentation section 4, that is, the processing liquid, reaches the overflow weir 17 on the downstream side. As described above, since the overflow weir 17 is provided slightly inclined on the side of the liquid sending tank unit 5, the flow of the processing liquid becomes the entire flow including the bottom of the settling unit 4, and Flow dam 17
The processing liquid that has exceeded the threshold value flows into the liquid sending tank unit 5.

The processing liquid temporarily stored in the liquid sending tank 5 is supplied to the outside of the apparatus via a processing liquid pipe 19.

As described above, the flocs deposited on the bottom of the sedimentation section 4 are periodically discharged out of the apparatus via the discharge line 15 by opening the discharge valve 16.

[0029]

As described above, according to the present invention, the first agitation unit, the second agitation unit, and the sedimentation unit are integrally provided, so that it is possible to provide a compact coagulation-sedimentation treatment apparatus.

[Brief description of the drawings]

FIG. 1 is an explanatory plan view schematically showing an entire coagulation / sedimentation treatment apparatus according to the present invention.

FIG. 2 is an explanatory side view schematically showing the entire coagulation / sedimentation treatment apparatus according to the present invention.

FIG. 3 is an enlarged cross-sectional explanatory view taken along the line III-III of FIG. 1, and is an enlarged cross-sectional explanatory view showing a portion of a rectifying wall and a collision plate in detail.

FIG. 4 is a cross-sectional explanatory view taken along the line IV-IV of FIG. 1, and is a cross-sectional explanatory view showing each inclined plate in detail.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Coagulation sedimentation processing apparatus 2 ... 1st stirring part 3 ... 2nd stirring part 4 ... Settling part 9 ... 1st partition 10 ... 2nd partition 11 ... Rectification wall 12 ... Communication hole 14 ... Inclined plate 20 ... Impact plate

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-8-112505 (JP, A) JP-A-51-98149 (JP, A) JP-A-54-99269 (JP, A) JP-A-51-98 145060 (JP, A) JP-A-49-19457 (JP, A) JP-A 50-149647 (JP, U) JP-A 58-73307 (JP, U) JP-A 50-121373 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B01D 21/00-21/34

Claims (3)

(57) [Claims] 1. A first stirring unit 2 for adding a flocculant to a stock solution, a second stirring unit 3 for forming flocs,
And precipitation unit 4 to precipitate the flocs, the second agitating
A plurality of communication holes 12, 1 for communicating the part 3 and the settling part 4
The second stirring section 3 and the precipitation section 4 forming 2,.
Rectifying wall 11 for partitioning the rectifying wall 11 and the settling portion of the rectifying wall 11
Collision plates provided on the four sides for the respective communication holes 12
20. A coagulation / sedimentation treatment apparatus comprising: 2. The coagulation sedimentation process according to claim 1, wherein the first stirring section 2 and the second stirring section 3 are partitioned by a partition, and an inclined plate 14 is provided in the settling section 4. apparatus. 3. The coagulation / sedimentation treatment apparatus according to claim 2, wherein the inclined plate 14 is provided in parallel with the liquid flow.