JP4503870B2

JP4503870B2 - Underwater air mixer

Info

Publication number: JP4503870B2
Application number: JP2001075274A
Authority: JP
Inventors: 宗宏澤田; 一夫飯坂
Original assignee: Tsurumi Manufacturing Co Ltd
Current assignee: Tsurumi Manufacturing Co Ltd
Priority date: 2001-03-16
Filing date: 2001-03-16
Publication date: 2010-07-14
Anticipated expiration: 2021-03-16
Also published as: JP2002273468A

Description

【０００１】
【発明の技術分野】
本発明は、汚水処理槽などで曝気撹拌のため使用される水中エアーミキサに関するものである。
【０００２】
【従来技術とその問題点】
従来の水中エアーミキサーは図５に示すよう、ドラフト環１０４のベルマウス状下方部と傘状整流板１０５との対向面間における外周部の全周方向へ亘る環状の吐水口１０７が開口され、且つ傘状整流板１０５と底板１０９との対向面間における外周部の全周方向へ亘る環状の散気口１１５が開口されており、軸流羽根車１０３の回転に伴い吸水口１０６から吸い込まれた水と空気導入管１０８から送り込まれた空気とが、それぞれ環状の吐水口１０７および散気口１１５の全周から放射状に放出されるため、吐き出しの流速が遅くて放出の距離は伸びず、エアーリフトによる空気の壁が水中エアーミキサに近い位置で環状に形成され、その干渉を受けて吸込み水流も少なくなると共に槽内における空気の滞留時間も短かくなり、十分な曝気撹拌効果を奏することができないという欠点がある。
【０００３】
【発明の目的】
本発明の目的は、吐き出し水流の流速が速くて放出の距離が長く、エアーリフトによる吸い込み側水流への干渉が少なく、且つ水流に乗った空気の到達距離も長くて槽内での空気の滞留時間が長く、十分な曝気撹拌効果の得られる水中エアーミキサを提供することにある。
【０００４】
【発明の構成】
本発明に係る水中エアーミキサにおいては、竪軸水中モータから導下された回転軸の下端部に軸流羽根車を装着し、羽根車の外周を囲繞するドラフト環の下方部をベルマウス状に外方へ拡張させ、該ドラフト環の下面と一定の間隔を保って対向する傘状の整流板を設けることにより、上端開口部を吸水口とし下端外周部を吐水口とする水流発生機構となし、下面中央部より空気導入管を開口させた底板を整流板の下方より対向させて空気室を形成させ、ドラフト環の前記ベルマウス状下方部と傘状整流板との対向面間における外周部に開口部と閉止部とを隔在させると共に、開口部が接線方向へ誘導された複数条の吐水溝となるよう仕切板を縦接し、空気室内から各吐水溝内に導入されて外周面へ開口される散気路を開設した。そして該散気路は各吐水溝の中央部溝底に沿って導延されていることが望ましい。
【０００５】
【実施例】
以下実施例の図１ないし図４により説明をする。
【０００６】
１は竪軸水中モータ、２は竪軸水中モータ１から導下された回転軸、３は回転軸２の下端部に装着された軸流羽根車、４は羽根車３の外周を囲繞するドラフト環であり、その下方部はベルマウス状に外方へ拡張された形態となっており、該ドラフト環４の下面と一定の間隔を保って対向する傘状の整流板５を設けることにより、上端開口部を吸込口６とし下端外周部を吐水口７とする水流発生機構が構成されている。８は空気導入管、９は下面中央部より空気導入管８を開口させた底板であり、該底板９を整流板の下方より対向させて空気室１０を形成する。そしてドラフト環４の前記ベルマウス状下方部と傘状整流板５との対向面間における外周部に開口部１１と閉止部１２とを隔在させ、且つ開口部１１・・１１が接続方向へ誘導された複数条の吐水溝１３・・１３となるよう仕切板14・・１４を縦設し、空気室１０内から各吐水溝１３・・１３内へ導入されて外周面へ開口される散気路１５・・１５を開設するが、これら散気路１５・・１５は各吐水溝１３・・１３の中央部溝底に沿って導延されていることが望ましい。
【０００７】
【作用】
本発明エアーミキサを曝気槽内へ設置して駆動させると、軸流羽根車３によって吸込口６からドラフト環４内へ吸込まれた水が仕切板１４・・１４に沿い吐水溝１３・・１３から強力な水流となって接線方向へ噴出され、また、空気導入管８を通って空気室１０内へ送り込まれた空気は吐水溝１３・・１３内の散気路１５・・１５を通って接線方向へ噴出され上記水流中に混入して微細気泡となり、エアーミキサから遠く離れたところで気液混合体が槽内に分布し、槽内における空気の滞留時間も長くなるのであるが、本発明エアーミキサにおける吐水溝１３・・１３および散気路１５・・１５は、ドラフト環４のベルマウス状下方部と傘状整流板５との対向面間における外周部の全周方向へ円周状に開口されているのでなく、開口部１１と閉止部１２を隔在させた態様で開設され、出口の開口面積が狭く絞られた状態となっているので、エアーリフトによる空気の壁が環状に形成されることがなく、吸込み側水流への干渉が少なくなり、前記槽内における空気の滞留時間が長いことと相俟って十分な曝気撹拌効果が得られることになる。また、散気路１５・・１５を各吐水溝１３・・１３の中央部溝底に沿って導延させた構造とすれば、空気が水流に囲まれた状態で排出されるため曝気作用は一層有効に行われることになる。
【０００８】
本発明エアーミキサによれば、吐き出し水流の速度が速くて放出の距離が長く、エアーリフトによる吸い込み側水流への干渉が少なくなり、且つ水流に乗った空気の到達距離も長くて槽内での滞留時間が長く、十分な曝気撹拌効果が得られるという利点がある。
【図面の簡単な説明】
【図１】本発明水中エアーミキサの構成を示した要部縦断側面図である。
【図２】本発明水中エアーミキサにおける整流板の平面図である。
【図３】本発明水中エアーミキサにおけるドラフト環、整流板および底板の外周縁部の展開図であって、散気路が吐水溝の溝底に沿って導延されている事例を示す。
【図４】本発明水中エアーミキサにおけるドラフト環、整流板および底板の外周縁部の展開図であって、散気路が吐水溝の中央部溝底に沿って導延されている事例を示す。
【図５】本発明水中エアーミキサにおける気液の噴出経路を示す説明図である。
【図６】従来の水中エアーミキサにおける気液の噴出経路を示す説明図である。
【符号の説明】
１竪軸水中モータ
２回転軸
３羽根車
４ドラフト環
５整流板
６吸水口
７吐水口
８空気導入管
９底板
１０空気室
１１開口部
１２閉止部
１３吐水溝
１４仕切板
１５散気路[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an underwater air mixer used for aeration and stirring in a sewage treatment tank or the like.
[0002]
[Prior art and its problems]
As shown in FIG. 5, the conventional underwater air mixer has an annular spout 107 that extends in the entire circumferential direction of the outer peripheral portion between the bellmouth-like lower part of the draft ring 104 and the umbrella-like rectifying plate 105. In addition, an annular air diffusion port 115 is opened over the entire circumference of the outer peripheral portion between the opposed surfaces of the umbrella-shaped rectifying plate 105 and the bottom plate 109, and is sucked from the water intake port 106 as the axial flow impeller 103 rotates. Water and air sent from the air introduction pipe 108 are discharged radially from the entire circumference of the annular spout 107 and the diffuser 115, respectively, and the discharge flow rate is slow and the discharge distance does not increase, The air wall by the air lift is formed in an annular shape at a position close to the underwater air mixer, and due to the interference, the suction water flow is reduced and the residence time of the air in the tank is shortened, so that sufficient aeration is performed. There is a disadvantage that it is impossible to achieve the 拌 effect.
[0003]
OBJECT OF THE INVENTION
The object of the present invention is that the discharge water flow has a high flow rate and the discharge distance is long, there is little interference with the suction-side water flow by the air lift, and the arrival distance of the air on the water flow is also long and the air stays in the tank. An object is to provide an underwater air mixer that takes a long time and can provide a sufficient aeration and stirring effect.
[0004]
[Structure of the invention]
In the submersible air mixer according to the present invention, an axial-flow impeller is attached to the lower end portion of the rotary shaft guided from the vertical shaft submersible motor, and the lower part of the draft ring surrounding the outer periphery of the impeller is removed in a bell mouth shape. By extending the direction toward the bottom and providing an umbrella-shaped rectifying plate facing the lower surface of the draft ring with a certain distance, there is a water flow generating mechanism with the upper end opening as the water inlet and the lower outer periphery as the water outlet. An air chamber is formed by making the bottom plate with the air introduction pipe open from the center of the lower surface to face the lower side of the rectifying plate, and on the outer peripheral part between the opposing surfaces of the bell mouth-like lower part of the draft ring and the umbrella-like rectifying plate In addition to separating the opening and the closing part, the partition plate is vertically connected so that the opening becomes a plurality of water discharge grooves guided in the tangential direction, and is introduced into each water discharge groove from the air chamber and opened to the outer peripheral surface. Established a diffuser that will be. And it is desirable for this air diffusion path to be extended along the center groove bottom of each water discharge groove.
[0005]
【Example】
The embodiment will be described below with reference to FIGS.
[0006]
1 is a vertical shaft submersible motor, 2 is a rotary shaft guided from the vertical shaft submersible motor 1, 3 is an axial impeller mounted on the lower end of the rotary shaft 2, and 4 is a draft surrounding the outer periphery of the impeller 3. It is a ring, and its lower part has a form expanded outward like a bell mouth, and by providing an umbrella-shaped rectifying plate 5 facing the lower surface of the draft ring 4 with a certain distance, A water flow generating mechanism is configured in which the upper end opening is the suction port 6 and the lower outer periphery is the water discharge port 7. Reference numeral 8 denotes an air introduction pipe, and 9 denotes a bottom plate in which the air introduction pipe 8 is opened from the center of the lower surface. The bottom plate 9 is opposed from below the rectifying plate to form an air chamber 10. And the opening part 11 and the closing part 12 are spaced apart by the outer peripheral part between the opposing surfaces of the said bellmouth-like lower part of the draft ring 4 and the umbrella-shaped rectifying plate 5, and the opening parts 11. The partition plates 14... 14 are vertically arranged so as to form a plurality of guided water discharge grooves 13.. 13 and are introduced from the air chamber 10 into the water discharge grooves 13. Although air passages 15 are opened, it is desirable that the air diffusion passages 15 are extended along the bottoms of the central portions of the water discharge grooves 13.
[0007]
[Action]
When the air mixer of the present invention is installed and driven in the aeration tank, the water sucked into the draft ring 4 from the suction port 6 by the axial-flow impeller 3 from the water discharge grooves 13. A strong water flow is ejected in the tangential direction, and the air fed into the air chamber 10 through the air introduction pipe 8 is tangent through the air diffusion paths 15... 15 in the water discharge grooves 13. In the air mixer of the present invention, the gas-liquid mixture is distributed in the tank at a distance from the air mixer, and the residence time of the air in the tank becomes long. The water discharge grooves 13... 13 and the air diffusion paths 15... Rather than opening 11 and Opened in a mode in which the stoppers 12 are spaced apart, and since the opening area of the outlet is narrowed, the air wall by the air lift is not formed in an annular shape, and the suction side water flow Interference is reduced, and a sufficient aeration and stirring effect is obtained in combination with a long residence time of air in the tank. Further, if the air diffusion passages 15,... 15 are made to extend along the bottom of the central portion of each water discharge groove 13,..., The air is discharged in a state surrounded by the water flow, so the aeration action is It will be done more effectively.
[0008]
According to the air mixer of the present invention, the speed of the discharge water flow is high, the discharge distance is long, the interference with the suction side water flow by the air lift is reduced, and the arrival distance of the air on the water flow is also long and stays in the tank There are advantages that the time is long and a sufficient aeration and stirring effect can be obtained.
[Brief description of the drawings]
FIG. 1 is a longitudinal side view of a main part showing a configuration of an underwater air mixer of the present invention.
FIG. 2 is a plan view of a current plate in the underwater air mixer of the present invention.
FIG. 3 is a development view of an outer peripheral edge portion of a draft ring, a current plate, and a bottom plate in the underwater air mixer of the present invention, showing an example in which an air diffusion path is led along a groove bottom of a water discharge groove.
FIG. 4 is a development view of an outer peripheral edge of a draft ring, a current plate, and a bottom plate in the underwater air mixer of the present invention, showing an example in which an air diffusion path is led along a central groove bottom of a water discharge groove.
FIG. 5 is an explanatory diagram showing a gas-liquid ejection path in the underwater air mixer of the present invention.
FIG. 6 is an explanatory diagram showing a gas-liquid ejection path in a conventional underwater air mixer.
[Explanation of symbols]
Reference Signs List 1 shaft submersible motor 2 rotating shaft 3 impeller 4 draft ring 5 current plate 6 water inlet 7 water outlet 8 air inlet tube 9 bottom plate 10 air chamber 11 opening 12 closing portion 13 water discharge groove 14 partition plate 15 air diffuser

Claims

An axial-flow impeller is attached to the lower end of the rotating shaft guided from the shaft submersible motor, and the lower part of the draft ring surrounding the outer periphery of the impeller is expanded outward in the form of a bell mouth. By providing an umbrella-shaped rectifying plate facing the lower surface at a certain distance, a water flow generation mechanism with the upper end opening as the water inlet and the lower end outer periphery as the water outlet is formed, and the air introduction pipe is opened from the center of the lower surface. An air chamber is formed by making the bottom plate faced from below the rectifying plate, and an opening and a closing portion are separated at the outer peripheral portion between the opposed surfaces of the bell mouth-like lower portion of the draft ring and the umbrella-like rectifying plate. In addition, the partition plate is vertically connected so that the openings become a plurality of water discharge grooves guided in the tangential direction, and an air diffusion path that is introduced into each water discharge groove from the air chamber and opened to the outer peripheral surface is opened. An underwater air mixer characterized by

2. The underwater according to claim 1, wherein the air diffusion path introduced from the air chamber into each water discharge groove and opened to the outer peripheral surface is led along the center groove bottom of each water discharge groove. Air mixer.