JPH0677748B2 - Horizontal axis type aerator - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a horizontal axis aerator for efficiently and uniformly aerating an aeration tank by uniformly mixing sewage.

[Conventional technology]

When treating wastewater containing organic substances such as sewage sewage and industrial wastewater, install an aerator in the aeration tank that forms an endless waterway such as an oblong circulation waterway or a double circular waterway, and dispose of the wastewater in the tank. A method of performing aeration, that is, aerobic fermentation treatment by continuously mixing and agitating sewage while continuously supplying air, that is, oxygen in the air, is practiced.

As an aerator applied to this method, for example, the actual Kaisho 59-
There is a horizontal axis type aerator shown in 150593.

This aerator has many stirring blades around the drive shaft,
This stirring blade is rotated in the vicinity of the liquid surface, and exhibits excellent performance in aeration and stirring and mixing. However, in the conventionally known horizontal shaft type aerator, the stirring blades have the same aeration performance and stirring performance over the entire width of the drive shaft, so that there are the following disadvantages.

In a double circular aeration tank having an endless water channel, two aerators are installed parallel to each other in a direction orthogonal to a straight line passing through the center of the tank,
The flow velocity at each point in the water channel was measured while operating the aerator by installing a current meter at required intervals from the inner circumference side to the outer circumference side of the water channel at a position slightly swirled from 0 °.

As shown in FIG. 2 (α = 0 °), it was found that the measurement results at the measurement points in FIGS. 1a, 1b, 1c, 1c and 1d are slower on the outer peripheral side of the water channel, and the flow velocity becomes faster at the outer peripheral side.

As described above, the uneven flow velocity in the water channel may cause sedimentation and accumulation of sludge and excessive aeration, which causes a new problem of deteriorating water quality.

[Problems to be Solved by the Invention]

In view of this, the present invention provides a horizontal axis type aerator capable of changing the aeration and agitation performance by the aerator in the transverse direction of the water channel according to the shape and size of the water channel. For evenness, mixing wastewater uniformly, sludge accumulation,
The purpose is to prevent deterioration of water quality and to perform efficient aeration.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the first invention is a horizontal shaft type aerator which is configured by arranging a large number of stirring blades around a drive shaft and is arranged across an endless water channel. The drive shaft is divided into a plurality of parts to drive the stirring blades independently for each drive shaft, and the drive shaft located on the inner peripheral side of the endless water channel is rotated faster than the drive shaft located on the outer peripheral side. That is the summary.

The second aspect of the present invention is a horizontal shaft type aerator that is configured by arranging a large number of stirring blades around a drive shaft and is arranged across an endless water channel. The end part of the endless water channel is rotatably supported so that the drive shaft on the inner peripheral side of the endless water channel is lower than the drive shaft on the outer peripheral side. Putting is the gist.

A third aspect of the present invention is a horizontal shaft type aerator that is configured by arranging a large number of stirring blades around a drive shaft and is arranged across an endless water channel, wherein the stirring blades are the drive shafts. The gist is that the inner peripheral side of the endless water channel has a large blade diameter in the axial direction and the outer peripheral side has a small blade diameter.

A fourth aspect of the present invention is a horizontal shaft type aerator configured by arranging a large number of stirring blades around a drive shaft and arranged across an endless water channel, wherein the drive shaft is not terminated. The gist is that the outer peripheral side is supported so as to be higher than the inner peripheral side of the water channel so that the stirring blade on the inner peripheral side of the endless water channel is placed deeper in water than the stirring blade on the outer peripheral side.

The fifth aspect of the present invention is a horizontal shaft type aerator that is configured by arranging a large number of stirring blades around a drive shaft and is arranged across an endless water channel, in which the water flow is in the endless water channel. The gist is that the drive shaft is axially supported on the downstream side in comparison with the inner peripheral side of the endless water channel so as to face the inner peripheral direction.

A sixth aspect of the present invention is a horizontal shaft type aerator that is configured by arranging a large number of stirring blades around a drive shaft, and is arranged across an endless water channel. The gist is that the mounting angle is to be an angle that the water flow is directed to the inner circumference of the endless water channel.

〔Example〕

Hereinafter, a homogeneous mixing aeration apparatus in the aeration tank of the present invention will be described based on the illustrated embodiment.

FIG. 1 shows an embodiment using a double circular aeration tank in which the endless water channel is circular.

Reference numeral 1 is a double circular aeration tank, in which a small-diameter circumferential wall 11 and a large-diameter outer circumferential wall 12 are concentrically arranged, and both inner and outer circumferential walls 11, 12 are provided.
An endless water channel 13 having a required width and depth is formed therebetween.

The aerator 2 installed in the endless water channel 13 is of a horizontal axis type and is installed so as to cross the water channel 13 as shown in FIG. At this time, the drive shaft of the aerator 2 is installed so that the outer peripheral side is axially supported on the downstream side as compared with the inner peripheral side of the endless water channel 13 so that the water flow is directed toward the inner peripheral side of the endless water channel 13. This mounting angle is α, this mounting angle α is changed to 0 ° and 9 °, and further, in the water channel 13 and at a position swiveled 180 ° or more from the set position of the aerator 2, and at a position 10 cm from the bottom. Flowmeters a, b, c, d installed
Then, the flow velocity at each position of the waterway was measured. The results are shown in FIG.

As can be seen from this, when α = 9 °, the flow velocities on the inner peripheral side and the outer peripheral side of the water channel 13 are substantially equalized. This indicates that the aerator 2 increases the flow velocity on the inner peripheral side of the endless water channel 13 more than the flow velocity on the outer peripheral side.

FIG. 3 shows an embodiment in which an oval aeration tank 3 having a straight water channel is used as the endless water channel.

Also in this case, similarly to the double circular aeration tank shown in FIG. 1, the drive shaft of the aerator 2 is compared with the inner peripheral side of the endless water channel 13 so that the water flow is directed to the inner peripheral side of the endless water channel 13. The outer peripheral side is rotatably supported on the downstream side.

What is shown in FIG. 4 shows different embodiments of the horizontal axis aerator 2. The figure is a front view of the horizontal axis aerator 2,
In the figure, the left side is the outer circumference side of the endless water channel, and the right side is the inner circumference side.

In Fig. 4 (a), the aerator 2 is divided into two units, two units are coaxially arranged adjacent to each other, and when the stirring blades have the same diameter, the rotation number of the aerator 2 on the inner peripheral side of the endless water channel is set to the outer peripheral side. It is faster than the one.

In Fig. 4 (b), two aerators 2, 2 with the same diameter divided into two are arranged adjacent to each other. In this case, the axial center position is changed and the water depth of the aerator 2 on the inner circumference side of the endless water channel is changed. Is made deeper to increase the flow velocity on the inner peripheral side of the endless water channel even at the same number of revolutions.

In FIG. 4 (c), two aerators 2, 2 divided into two are arranged coaxially adjacent to each other so that they can be rotated at the same number of revolutions. In this case, the stirring blades are in the direction of the drive shaft. In addition, the inner diameter of the endless water channel is large and the outer diameter is small.

FIG. 4 (d) shows a case where the aerators 2, 2 having different diameters are rotated at the same water depth and at the same speed. Even if the water depth is the same, the diameters of the blades are different and the inner diameter is large, so the peripheral speed is substantially high and the flow speed on the inner diameter side can be increased.

FIG. 4 (e) is a configuration in which the rotational speeds of the two aerators 2, 2 are adjusted via the transmission in the embodiment of FIG. 4 (a).

4 (f) and 4 (g), the flow velocity on the inner peripheral side of the endless water channel is increased by changing the cross-sectional shape of the blade of the aerator 2.

In FIG. 4 (h), the drive shaft of the aerator 2 is axially supported so that the outer peripheral side is higher than the inner peripheral side of the endless water channel, so that the stirring blades on the inner peripheral side of the endless water channel are By placing it in water deeper than the stirring blades on the outer peripheral side, the flow velocity on the inner peripheral side of the endless water channel is increased.

FIG. 4 (i) shows the flow velocity on the inner circumference side of the endless water channel by setting the mounting angle of the stirring blade 2a of the aerator 2 to the drive shaft so that the water flow is directed toward the inner circumference of the endless water channel. It is designed to be increased.

〔The invention's effect〕

According to the present invention, since the horizontal axis type aerator is configured such that the flow velocity by the aerator is larger on the inner peripheral side than on the outer peripheral side of the endless water channel, the flow velocity across the water channel is increased. It is possible to make uniform, and by mixing sewage uniformly, preventing sludge accumulation and water quality deterioration,
There is an advantage that sewage can be stably and efficiently aerated.

[Brief description of drawings]

The drawing is an embodiment showing a homogeneous mixing aeration method in the aeration tank of the present invention. Fig. 1 is a plan view of a double circular aeration tank, and Fig. 2 is a graph showing the flow velocity value at each point of a water channel. FIG. 3 is a plan view of an oval aeration tank, and FIG. 4 is a front view of a horizontal axis type aerator of a different embodiment. 1 is a double circular aeration tank, 2 is a horizontal axis type aerator, and 3 is an oval aeration tank.

Continuation of the front page (56) Reference JP-A-60-71091 (JP, A) Actual opening 61-111599 (JP, U) Actual opening 61-64397 (JP, U) Actual opening Sho-60-21397 (JP , U) Actually open 55-31444 (JP, U) Actually open 59-131295 (JP, U)

Claims (6)

[Claims] 1. A horizontal shaft type aerator having a large number of stirring blades arranged around a drive shaft and arranged across an endless water channel, wherein the drive shaft is divided into a plurality of parts. The horizontal axis type is characterized in that the agitating blades are independently driven for each drive shaft, and the drive shaft located on the inner peripheral side of the endless water channel is rotated faster than the drive shaft located on the outer peripheral side. Aerator. 2. A horizontal shaft type aerator which is constructed by arranging a large number of stirring blades around a drive shaft and is arranged across an endless water channel, wherein the drive shaft is divided into a plurality of parts. Support the inner circumference side drive shaft of the endless water channel so that it is lower than the outer circumference side drive shaft, so that the stirring blade on the inner circumference side of the endless water channel is placed deeper in the water than the stirring blade on the outer circumference side. A horizontal axis aerator featuring. 3. A horizontal shaft type aerator which is constructed by disposing a large number of stirring blades around a drive shaft and is arranged across an endless water channel, wherein the stirring blades are oriented in the direction of the drive shaft. A horizontal axis type aerator characterized in that the inner diameter of the endless water channel is large and the outer diameter is small. 4. A horizontal shaft type aerator constructed by disposing a large number of stirring blades around a drive shaft and arranged across an endless water channel, wherein the drive shaft is located in the endless water channel. A horizontal axis aerator characterized in that the outer peripheral side is axially supported so as to be higher than the peripheral side, and thus the stirring blade on the inner peripheral side of the endless water channel is placed deeper in water than the stirring blade on the outer peripheral side. . 5. A horizontal shaft type aerator which is configured by arranging a large number of stirring blades around a drive shaft and is arranged across an endless water channel, wherein the water flow is directed toward the inner circumference of the endless water channel. The horizontal shaft type aerator is characterized in that the drive shaft is axially supported on the downstream side in comparison with the inner peripheral side of the endless water channel. 6. A horizontal shaft type aerator constructed by disposing a large number of stirring blades around a drive shaft and arranged across an endless water channel, wherein the stirring blades are attached to the drive shaft. A horizontal axis aerator characterized in that the angle is such that the water flow is directed toward the inner circumference of the endless water channel.