JPS629929Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a sedimentation and concentration apparatus that can effectively concentrate sludge that is difficult to thicken.

Conventional sludge thickening equipment sediments and concentrates sludge by simple gravity sedimentation, so biological flocs (excess sludge from activated sludge, blue-green algae, etc.) and metal hydroxides have poor sedimentation and concentration properties and are easily removed. has the disadvantage that it cannot be concentrated.

The present invention eliminates these drawbacks and allows difficult-to-thicken sludge to be effectively processed using a compact device.
It is an object of the present invention to provide a useful wastewater treatment device that can perform both filtration and sludge concentration functions and can stably concentrate and obtain a clear liquid.

The present invention has a sedimentation tank with a treated water outflow pipe at the top, a sludge pit at the center of the bottom, and a sludge drainage pipe communicating with the sludge pit. A cylindrical partition wall is disposed concentrically and perpendicularly to the tank wall of the settling tank to partition a raw water supply chamber and a clarification/separation section, and a raw water supply pipe is opened and disposed in the raw water supply chamber, and the An annular filter bed is formed on the outside of the sludge pit, a filtrate collection part is provided at the bottom of the filter bed, a sludge scraper is provided in the upper part of the filter bed and in the sludge pit, and a sludge scraper is provided outside the settling tank. A filtrate storage tank is provided, and the filtrate storage tank and the filtrate collection section are communicated via a filtrate collection channel.

To explain the embodiment of the present invention with reference to the drawings, the tank 4
A treated water outflow pipe 1 is installed at the top of the tank 4, a sludge pit 2 is installed at the center of the bottom, and a sludge drainage pipe 3 is installed to communicate with the pit. By arranging the partition wall 5 concentrically and vertically with the tank wall 4' of the tank 4, a raw water supply chamber 6 and a clarification/separation section 7 are partitioned into the tank 4, and the raw water supply chamber 6 is provided with raw water. The tube 8 is arranged in an open manner. The sludge pit 2 has a cylindrical partition wall 9a provided vertically.
(arranged concentrically with the tank wall 4'), and a mud removal pit 2b formed by an inverted conical partition wall 9b continuous to the lower part of the partition wall 9a. There is. Further, the outer annular portion of the partition wall 9a is filled with gravel, sand, etc. to form a floor 10, and a plurality of water collection pipes 11 as the liquid collection portion are arranged radially at the bottom of the floor 10, and a tank A liquid collecting channel 13 is formed by surrounding the inner periphery of the bottom of the tank 4 with a partition wall 12, and the collecting channel is communicated with a liquid storage tank 14 provided outside the tank 4, so that the liquid level L' of the storage tank is always equal to the liquid level L' of the tank 4. a liquid discharge pump 15 for ensuring that the liquid level is sufficiently below the liquid level L of
(for example, a submersible pump), and a scraper 16 for scraping the sludge on the surface of the floor 10 into the sludge collecting pit 2a and discharging the concentrated sludge D from the sludge draining pipe 3. It is becoming.

The pump 15 is disposed at the bottom of the liquid storage tank 14, and is connected to a level switch for controlling the liquid level L' so that it is always near the bottom. Similarly, a level switch is connected to a raw water supply pump (not shown) connected to the raw water supply pipe 8 to control the liquid level L of the tank 4 to be slightly lower than the upper end of the tank wall 4'. ing.

Thus, the raw water A is supplied from the raw water supply pipe 8 to the raw water supply chamber 6 and is evenly distributed within the tank 4. After the sludge in the raw water A settles and settles on the upper part of the bed 10, it is scraped up into the sludge collection pit 2a by the scraper 16, and is discharged from the sludge pipe 3 to the outside of the system via the sludge pit 2b. On the other hand, the liquid C is discharged out of the system by the pump 15 through the water collection pipe 11 and the liquid collection channel 13. Further, the supernatant water B is discharged from the treated water outflow pipe 1.

In this case, the sludge on the bed 10 is effectively concentrated because, in addition to the sludge's own weight, consolidation pressure is applied due to the difference between the liquid levels L and L'.

In the embodiment described above, the sludge pit 2b has a shape that protrudes downward from the bottom plate 4'' of the tank 4, but the bottom plate 4'' is made into a flat plate for the entire tank 4, and only the partition wall 9b or the partition wall is placed on the bottom plate 4''. 9a and 9b may be installed in a continuous manner.Furthermore, the water collection pipe 11 may be a ring-shaped water collection chamber.

As mentioned above, the sludge thickening device of the present invention is a conventional sludge thickener with a new forced thickening mechanism based on the water head difference, so it is not only caused by gravity settling but also by the downward force caused by the liquid passing through the sludge layer. Because it involves the consolidation action of the sludge layer based on the conventional method, it is possible to effectively concentrate the difficult-to-thicken slurry that is difficult to thicken in the past, and the sludge concentration is significantly increased compared to the conventional type, thereby significantly streamlining the subsequent sludge treatment process. In addition, a filtrate storage tank is provided that communicates with the filtrate collection section through a filtration collection channel, where the amount of filtration decreases when the pressure is increased, and the water surface can be freely adjusted depending on the type of sludge. By controlling the filtration pressure, it is possible to effectively concentrate and dewater difficult-to-filter sludge, where the amount of filtration decreases when the amount of filtration increases.
The advantages include that overaction and sedimentation/separation can be carried out smoothly in a single tank, and that the entire apparatus is compact and simple in structure.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view showing an embodiment of the present invention. 1... Treated water outflow pipe, 2... Sludge pit, 2a
...Mud collecting pit, 2b...Sludge removal pit, 3...Sludge removal pipe, 4...Tank, 4'...Tank wall, 4''...Bottom plate, 5
... Partition wall, 6 ... Raw water supply chamber, 7 ... Clarification separation section, 8 ... Raw water supply pipe, 9a, 9b ... Partition wall, 1
0...Floor, 11...Water collection pipe, 12...Bulkhead, 1
3...Liquid collection channel, 14...Liquid storage tank, 15...
...pump, 16... scraper.

Claims (1)

[Scope of utility model registration request] The sedimentation tank is equipped with a treated water outflow pipe at the top, a sludge pit at the center of the bottom, and a drainage pipe communicating with the sludge pit. A cylindrical partition wall is disposed concentrically and vertically with the tank wall to partition a raw water supply chamber and a clarification/separation section, and a raw water supply pipe is opened in the raw water supply chamber, and the outside of the sludge pit is provided with a raw water supply pipe. A ring-shaped filter bed is formed in the filter bed, a filtrate collection part is provided at the bottom of the filter bed, a sludge scraper is provided in the upper part of the filter bed and in the sludge pit, and a filtrate storage tank is provided outside the settling tank. A wastewater treatment apparatus characterized in that the filtrate storage tank and the filtrate collection section are provided in communication with each other via a filtrate collection channel.