Gas and liquid contact apparatus – Contact devices – Rotating
Reexamination Certificate
2000-02-18
2002-02-12
Bushey, C. Scott (Department: 1724)
Gas and liquid contact apparatus
Contact devices
Rotating
C261S093000
Reexamination Certificate
active
06345810
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an aerating unit, more particularly to an aerating unit for treating a body of waste water.
2. Description of the Related Art
Processes for aerobic biotreatment of municipal or industrial waste water or sewage had been well developed. The known processes involve a preliminary treatment which separates floating larger particles, organic solid suspensions, or oil from a body of waste water, an intermediate treatment which includes an aerating unit that provides oxygen to be dissolved in the body of waste water for allowing active sludge to decompose aerobically organic compounds dissolved in the body of waste water, and a final treatment which includes a sedimentation apparatus for precipitating solid particles to separate the treated waste water from the precipitates. The aerating unit is normally designed to provide fine air bubbles dispersed in the body of waste water so as to replenish continually the waste water with dissolved oxygen to enhance the aerobic biotreatment. The retention time and the size of the air bubbles generated by the aerating unit are very important factors to ensure effective dissolution of the oxygen in the waste water.
FIG. 1
illustrates a conventional aerating unit which includes a plurality of disk-shaped diffusers
14
mounted in a container
1
which contains a body of waste water. The diffusers
14
are connected to an air blower
12
via a pipeline
11
. Each diffuser
14
is formed with a plurality of small apertures for generating air bubbles dispersed in the body of waste water when the air blower
12
is activated. Since the air bubbles thus formed rise straightly by virtue of buoyancy, the air bubbles generated by each diffuser
14
in the body of waste water are dispersed within a relatively narrow area, and the retention time of the air bubbles is relatively short, thereby necessitating the use of many diffusers
14
in the container
1
.
FIG. 2
illustrates another conventional aerating unit which is similar to the above described aerating unit except that an agitating device
26
is mounted in a container
2
above a plurality of diffusers
25
. The agitating device
26
pushes waste water downwardly to mix with rising air bubbles generated by the diffusers
25
, and provides turbulence in the body of waste water so as to enhance the dispersion of the air bubbles when the agitating device
26
is actuated. While the dispersion of the air bubbles in the body of waste water can be enhanced by utilizing the agitating device
26
, the dispersion of the air bubbles in the body of waste water is still unsatisfactory. Moreover, the diffusers
25
are normally spaced apart by a relatively long distance from the bottom of the container
2
, thereby decreasing the retention time of the air bubbles.
FIG. 3
illustrates yet another conventional aerating unit
3
which includes a submersible motor
31
immersed in a body of waste water, an air housing
33
connected to the motor
31
and extending downwardly therefrom, an air conduit
34
connected to the air housing
33
and extending upwardly therefrom and through the surface of the waste water, and a diffuser
36
connected to the air housing
33
and extending downwardly therefrom. The diffuser
36
is formed with a plurality of openings
35
. The submersible motor
31
has a shaft extending downwardly therefrom into the air housing
33
. The shaft is provided with a propeller
32
within the air housing
33
for introducing air into the diffuser
36
from above the surface of the waste water via the air conduit
34
and the air housing
33
, and for driving air out of the diffuser
36
to form fine air bubbles dispersed in the body of waste water when the shaft is rotated. The horsepower of the submersible motor
31
must be adequate to overcome a water head from the diffuser
36
to the surface of the waste water in order to suck atmospheric air into the air housing
33
and to drive the air out of the diffuser
36
. However, the deeper the location of the aerating unit
3
in the body of waste water, the larger will be the horsepower requirement for the submersible motor
31
to ensure sufficient air flow into the body of waste water.
SUMMARY OF THE INVENTION
Therefore, it is an object of the present invention to provide an aerating unit that is capable of overcoming the aforementioned problems commonly associated with the prior arts.
Accordingly, an aerating unit of this invention is adapted to treat a body of waste water and comprises: a container adapted for storing the body of waste water; a submersible motor disposed in the container and having a shaft extending downwardly and outwardly therefrom into the body of waste water, the shaft having a bottom free end provided with a propeller; an air conduit adapted to be connected to an air supply at one end, and extending into the container at the other end which defines an air outlet adjacent to and facing toward the propeller, the air conduit being adapted to introduce air into the body of waste water stored in the container, thereby generating larger air bubbles inside the container that are directed toward the propeller, the motor being operable so as to enable the propeller to break the larger air bubbles into finer air bubbles that are directed downwardly; and a base disposed vertically below and aligned with the motor in the container, the base having a curved surface which is convex in a direction toward the propeller for deflecting the finer air bubbles directed from the propeller in radial directions of the curved surface in the body of waste water.
REFERENCES:
patent: 2077445 (1937-04-01), Wallace et al.
patent: 2130402 (1938-09-01), Textor
patent: 3385576 (1968-05-01), Wikswo
patent: 3814395 (1974-06-01), Kaelin
patent: 4066722 (1978-01-01), Pietruszewski et al.
patent: 4259267 (1981-03-01), Wang
patent: 4290885 (1981-09-01), Kwak
patent: 4350648 (1982-09-01), Watkins, III et al.
patent: 4358413 (1982-11-01), Brucker
patent: 4734235 (1988-03-01), Holyoak
patent: 6050550 (2000-04-01), Burgess
patent: 59-92093 (1984-05-01), None
patent: 1238803 (1986-06-01), None
Bushey C. Scott
Townsend and Townsend / and Crew LLP
LandOfFree
Aerating unit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Aerating unit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Aerating unit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2954304