JPH0123595Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention is a filter material for wastewater treatment that is filled into a wastewater treatment tank that purifies wastewater by the action of microorganisms, and serves as a medium for epiphytic propagation of the microorganisms. It is related to.

(Prior art) Methods for biochemically purifying wastewater such as organic sewage can be broadly divided into aerobic treatment methods that utilize the action of aerobic microorganisms, and anaerobic treatment methods that utilize the action of anaerobic microorganisms. Various types of filter media have been developed for use in these applications. For example, Japanese Utility Model Publication No. 56-21520 discloses that a first group of semicircular blades and a second group of blades are arranged such that each blade is orthogonal to each other as shown in the figure and has a spherical outline. A filter medium constructed as shown in FIG.

(Problem that the invention aims to solve) By the way, the performance required of this type of filter medium is that for aerobic treatment, it must have a large specific surface area to increase the amount of microbial sludge attached, and it must have a high sewage circulation efficiency. The porosity is large to improve the
In addition to the above requirements, in the case of anaerobic treatment, the filter media must be easy to fill and inexpensive.
It is required to have a shape that does not cause clogging or drift due to sludge, to be easy to remove sludge during backwashing, and to have a specific gravity of more than 1.0, but not too heavy.

However, all conventional filter media have performance that is suitable only for either aerobic treatment or anaerobic treatment, and none have all the performance required for both, making them lacking in versatility. There was a problem. For example, although the filter medium disclosed in Utility Model Publication No. 56-21520 has the performance of the former,
Due to the structure, the directionality of the flow causes drift,
The latter performance is not perfect.

(Means for Solving the Problems) The wastewater treatment filter medium of the present invention is formed by combining a plurality of synthetic resin plates, and the outer edges of the plates have a substantially spherical outline. A substantially spherical cavity is formed inside, and the cavity is communicated with the outside through passages between the plates.

(Function) It has all the performances required for aerobic treatment and anaerobic treatment as described above, such as having an almost spherical cavity inside and not causing drifting.
In particular, when the specific gravity is 1.0 to 1.05, the sludge sinks in the sewage treatment layer, and when backwashed with air, it floats while rotating due to its almost spherical shape, making it easy to remove the sludge.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

A filter medium for wastewater treatment according to the present invention is shown in FIGS. 1 to 3, and the filter medium 1 is made of synthetic resin and has a spherical outline as a whole. Two ring-shaped plates 3 are combined to form a wastewater treatment device 4, as shown in FIG.
Each tank (anaerobic filter bed tank) 5, 6, 7 is filled with a large number of anaerobic filters.

A plurality of first plates 2 intersect on a single axis A and have the same center B.
These first ring-shaped plates 2... are crossed at equal angles θ as shown in FIG. 3, and in the illustrated example, the three ring-shaped plates 2...
intersect at an angle of degree.

The second ring-shaped plate 3 is of the same shape and size as the first ring-shaped plate 2, and its center coincides with the center B, and the second ring-shaped plate 3 is similar to the first ring-shaped plate 2. 2. It is arranged to intersect perpendicularly to all of... A small-diameter ring-shaped plate whose outline is approximately spherical may be provided parallel to the second ring-shaped plate 3.

Further, a trapezoidal reinforcing plate 1 is provided at the intersection of the first ring-shaped plate 2 and the second ring-shaped plate 3.
0 is provided in an upright manner, thereby reinforcing the strength of this portion and increasing the specific surface area.

Further, the reinforcing plates 10 work together with the second ring-shaped plate body 3 to prevent the filter media 1 filled in the wastewater treatment device 4 from jamming together. Note that the plate forming the filter medium 1 is not limited to a ring shape.
It may also be formed by combining a plurality of arch-shaped plates.

Therefore, in the filter medium 1 configured as described above, the outer edge 2a of the first ring-shaped plate 2...
..., and the outer edge 3a of the second ring-shaped plate body 3...
has a substantially spherical outline, and a cavity 11 is formed inside the inner edge 2 of the first ring-shaped plate 2.
b, and the inner edge 3b of the second ring-shaped plate 3. The hollow portion 11 has a substantially spherical shape having the same center B as the substantially spherical shape formed by the outer edge 2a of the first ring-shaped plate 2 and the outer edge 3a of the second ring-shaped plate 3. With,
It is communicated with the outside through a passage 20 formed by a gap between each of the first ring-shaped plates 2 and the second ring-shaped plate 3, and the passage 20 is connected to the center B.
It is preferable that it be radial with respect to.

The number of the first ring-shaped plates 2 and the second ring-shaped plates 3 is set in consideration of the porosity and specific surface area between each plate, and the specific gravity is
The specific gravity is preferably 1.0 to 1.05, and for example, for anaerobic treatment, the specific gravity is preferably about 1.03.

As shown in FIG. 4, the wastewater treatment device 4 using the anaerobic treatment method includes a plurality of tanks such as a first anaerobic filter bed tank 5, a second anaerobic filter bed tank 6, and a third anaerobic filter bed tank 7. A net-like floor 12 is provided inside the
A large number of the filter media 1 are filled on top of this to form a packed layer. At this time, if the filter medium 1 is filled after filling with water, the directions will be automatically aligned and the gaps will be approximately equal. Moreover, the filter medium 1 to be filled is the first
As the anaerobic filter bed tank 5, the second anaerobic filter bed tank 6, and the third anaerobic filter bed tank 7 are moved, the spherical diameter is set smaller; for example, in the case of the first anaerobic filter bed tank 5, it is 140 mm;
In the case of the second anaerobic filter bed tank 6, the length is 100 mm, and in the case of the third anaerobic filter bed tank 7, it is 80 mm. In addition, 13
is an air backwashing device for sludge removal, 14 is floor 1
15 a discharge pipe for discharging sludge accumulated on the lower side of 2;
is the exhaust pipe.

Therefore, the wastewater introduced from above into the first anaerobic filter bed tank 5 flows down the packed bed of filter media 1, and then sequentially overflows to the second anaerobic filter bed tank 6 and then to the third anaerobic filter bed tank. 7, and similarly to the inside of the first anaerobic filter bed tank 5, the filter media 1 are purified by flowing down the packed layers of the filter media 1. At this time, the treated water flowing down the packed bed passes between the ring-shaped plates of each filter medium 1, enters the cavity 11, and then passes between the ring-shaped plates and returns to the outside of the filter medium 1. Since the flow is not obstructed in any way, the flow is uniformly distributed throughout the packed bed without any uneven flow between the filter media.
Thereby, the entire treated water comes into contact with the ring-shaped plate of each filter medium 1 efficiently.

The filter medium 1 described above may be integrally molded from synthetic resin by injection molding, and the structure is not limited to the illustrated example, but may be modified as long as it has at least a spherical cavity inside.

(Effects of the invention) As detailed above, according to the present invention, various excellent effects as described below can be obtained.

(1) Since it has an almost spherical outline as a whole, close packing is possible, and the specific surface area of the packed layer can be made extremely large.

(2) Since it is constructed by combining ring-shaped plates, it has a large porosity, high wastewater circulation efficiency, and is less likely to become clogged.

Since they are almost spherical, they can be arranged at even density even if they are filled casually, making the filling operation easy.

Since there is an almost spherical cavity inside, drifting does not occur.

When the specific gravity is 1.0 to 1.05, it will sink and easily float up when air flows backward, making it easy to peel off the sludge.

Since it is made of synthetic resin, it is inexpensive, and
It has excellent corrosion resistance and has a semi-permanent service life.

That is, the filter medium of the present invention has both the performance required for aerobic treatment and the performance required for anaerobic treatment, and is highly versatile.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is a perspective view showing a filter medium for wastewater treatment, Fig. 2 is a front view of the same as seen from the direction of the arrow in Fig. 1, and Fig. 3 is a plan view of the same. FIG. 4 is a block diagram showing a part of a purification device to which the same filter medium is applied. 2... First ring-shaped plate, 3... Second ring-shaped plate, 2a, 3a... Outer edge, 11... Cavity.

Claims (1)

[Scope of utility model registration request] It is made by combining a plurality of plates made of synthetic resin, and the outer edge of the plate has an approximately spherical outline, and an approximately spherical cavity is formed inside, and the cavity is formed between each plate. A filter medium for wastewater treatment, characterized in that the filter medium is communicated with the outside through a passageway between the two.