JP2000185245A - Aerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a pressure loss in the introduction of gas and the cracks of slits by a method in which in an aerator in which pressurized gas is supplied from numbers of the slits formed in an expandable sheet into liquid to generate a lot of bubbles in the liquid, the slits are formed in the shape of a nonstraight line. SOLUTION: In an aerator 1, a disk-shaped base 3 having a cylindrical part 2 in the middle is mounted on the upper surface of a frame 4. The upper end of the cylindrical part 2 is closed by a check valve 5 comprising a flexible synthetic resin plate, and the base 3 and the valve 5 are covered with a sheet 8 of a flexible synthetic resin. By introducing pressurized gas into the lower end of the cylindrical part 2, the valve 5 is opened, and fine bubbles 11 are generated through the slits 10 of the sheet 8. In this process, the slits 10 are formed in the shape of a non-straight line and operated as a cantilever beam with its one end fixed, and its middle part is vibrated. Accordingly fine bubbles 11 can be generated, and,the generation of cracks at both ends of the slits 11 can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aeration apparatus, and more particularly to an aeration apparatus having a membrane provided with slits, for aeration for biological filtration or ozone oxidation treatment such as activated sludge treatment, household wastewater treatment and human waste treatment. The present invention relates to an aeration device that can be used in places requiring aeration, such as moats, lakes and mars, and fish ponds.

[0002]

2. Description of the Related Art Conventionally, an aeration apparatus for performing a standard activated sludge method generally employs a swirling flow arrangement, and the amount of air supplied is 3 to 7 at an effective water depth of about 4 to 8 m with respect to the amount of sewage. Double is needed.

[0003] The aeration device is a device for supplying oxygen necessary for activated sludge microorganisms by blowing air sent from a blower into fine air bubbles into a sludge tank. Generally, a porous aeration device made of ceramics is used. Many tubes and plates made of rubber and synthetic resin are known.

For example, in an air diffuser disclosed in Japanese Patent Application Laid-Open No. 61-245857, gas is press-fitted into a flexible synthetic resin pipe in which a number of straight slits are cut in a pattern as shown in FIGS. As a result, the flexible material expands and contracts, and the linear slit portion opens and closes as shown in FIG. 13, and fine bubbles are continuously released into the liquid through the gap.

[0005]

However, as described above, in the aeration apparatus, since the slit portion is linear, the slit cannot be opened unless a certain pressure or more is applied, so that the pressure loss is large, and the expansion and contraction is further increased. Each time, the slit in Figure 1
As shown in FIG. 3, when tensile stress repeatedly acts in the directions of e, f, g, and h, a crack may be generated at both ends of the slit, and the slit may be torn and become unusable.

Further, in the case of this device, when the intermittent operation is performed, impurities in the liquid enter the slit due to water pressure and cause clogging, resulting in a marked decrease in aeration ability.
If used for a long time, the material may crack due to a change in temperature and may be damaged.

SUMMARY OF THE INVENTION The present invention provides an aeration apparatus capable of reducing energy loss of a blower in operation by reducing pressure loss when gas is injected and reducing cracks in slits and improving durability of a product. The purpose is to provide.

[0008]

According to the aeration apparatus of the present invention, a large number of air bubbles are formed in a liquid by forming a large number of slits in a stretchable sheet and passing a pressurized gas through the liquid through the slits. In the aeration apparatus configured to form the slit, the shape of the slit is non-linear.

Further, the slit is arc-shaped or mountain-shaped.

[0010] The sheet is wound around and fixed to both ends of the cylindrical body, and the both ends of the cylindrical body are connected by a connecting portion having a U-shaped cross section.

[0011]

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

(Example 1)

FIGS. 1 and 2 show a dome-shaped aeration apparatus 1 according to an embodiment of the present invention. In this apparatus, for example, a disk-shaped base 3 having a cylindrical portion 2 in the center and having a diameter of 280 mm, for example.
Is placed on a frame 4, the upper end of the cylindrical portion 2 is closed by a check valve 5 made of a flexible synthetic resin plate, and the central portion of the check valve 5 is held by a holding plate 6 and a screw 7.
The base 3 and the check valve 5 are covered with a flexible synthetic resin sheet 8 having a thickness of, for example, 1 mm, and the outer peripheral edges of the sheet 8, the base 3 and the frame 4 are fixed to each other by a fixture 9. The entire surface of the sheet 8 is, for example, 1.5 mm in radius and 80 °, for example, as shown in FIGS.
Are formed in a zigzag pattern at intervals of, for example, 4 mm.

As shown in FIG. 4, the slit 10 has a length of 1.5 m which is bent at an angle of, for example, 140 °.
It may be a slit of m.

Since the aeration apparatus of the present invention has the above configuration, if a pressurized gas is introduced into the lower end of the cylindrical portion 2, the check valve 5 opens as shown in FIG. Fine bubbles 11 are generated through the slits 8.

In this case, the slit 10 performs the same operation as a cantilever having one end fixed as shown in FIG. 6, so that the central portion of the slit 10 vibrates, and as a result, finer bubbles 11 are generated. As a result, cracks do not occur at both ends of the slit 10.

The shape of the slit 10 is not limited to the arc shape or the mountain shape, but may be any shape as long as it is non-linear. For example, one side of the mountain-shaped slit may be arcuate.

(Embodiment 2)

FIGS. 7 to 10 show another embodiment of the present invention in which the present invention is applied to a tube type aerator. In this embodiment, the sheet 8 is attached to the cylindrical ends 12a and 12b which are separated from each other. The cylindrical body 1 is wound and fixed to the cylindrical body ends 12a and 12b by a band 13, and the cylindrical body ends 12a and 12b are connected by a connecting portion 12c.
2 is formed so that the shape of the connecting portion 12c is such that its central portion rises in a U-shape to the vicinity of the central axis of the cylindrical body 12.

Reference numeral 14 denotes a space surrounded by the cylindrical body 12 and the end portion of the sheet 8, and reference numeral 15 denotes a pressurizing portion provided in the axial direction at the center of the one cylindrical end portion 12a and communicating with the space 14. The gas introduction holes 16 are located between the introduction hole 15 and the space 1.
This is a check valve inserted between the four.

In the second embodiment of the present invention, in addition to obtaining the same effects as those of the first embodiment, it is possible to prevent the cylinder 12 from being bent by water pressure.

[0022]

As described above, according to the aeration apparatus of the present invention, the power consumption of the operating blower is reduced by reducing the pressure loss in the aeration apparatus, and the sheet is not pressed when the gas is injected. Reducing the expansion and contraction has great advantages, such as reducing the cracks in the slits and improving the durability of the product.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view of an aeration apparatus of the present invention.

FIG. 2 is a plan view of the aeration apparatus of the present invention.

FIG. 3 is an explanatory view of a slit shape of the aeration apparatus of the present invention.

FIG. 4 is an explanatory view of another slit shape of the aeration apparatus of the present invention.

FIG. 5 is a vertical sectional front view for explaining the operation of the aeration apparatus of the present invention.

FIG. 6 is an enlarged view of a main part of FIG. 5;

FIG. 7 is a front view of another embodiment of the aeration apparatus of the present invention.

FIG. 8 is a vertical sectional front view of the aeration apparatus shown in FIG. 7;

FIG. 9 is a side view of the aeration apparatus shown in FIG. 7;

FIG. 10 is a sectional view taken along line GG of FIG. 7;

FIG. 11 is an explanatory view of a slit pattern of a conventional aeration apparatus.

FIG. 12 is an explanatory diagram of another example of the slit pattern of the conventional aeration apparatus.

FIG. 13 is an operation explanatory view of a slit of a conventional aeration apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aeration apparatus 2 Cylindrical part 3 Base 4 Frame 5 Check valve 6 Suppression plate 7 Screw 8 Sheet 9 Fixture 10 Slit 11 Bubble 12 Cylindrical body 12a Cylindrical end part 12b Cylindrical end part 12c Connecting part 13 Band 14 Space 15 Inlet 16 Check valve

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Koichi Kato 149 Hanashima-cho, Hanamigawa-ku, Chiba-shi, Chiba F-term (reference) in Monobe Engineering Co., Ltd. 4D029 AA01 AB07 BB10 BB11 BB13 4F033 AA00 BA02 CA07 DA01 EA05 FA00 GA06 NA01

Claims (4)

[Claims] 1. An aerator according to claim 1, wherein a plurality of slits are formed in the stretchable sheet, and a plurality of air bubbles are formed in the liquid by passing a pressurized gas through the liquid through the slits. An aeration apparatus characterized in that the slit has a non-linear shape. 2. The aeration apparatus according to claim 1, wherein said slit has an arc shape. 3. The aeration apparatus according to claim 1, wherein the slit has a mountain shape. 4. The sheet according to claim 1, wherein the sheet is wound and fixed at both ends of the cylindrical body, and the both ends of the cylindrical body are connected by a connecting portion having a U-shaped cross section. 3. The aeration apparatus according to 3.