JP3605683B2

JP3605683B2 - Wastewater treatment equipment using microorganisms

Info

Publication number: JP3605683B2
Application number: JP3030798A
Authority: JP
Inventors: 金一高橋
Original assignee: 株式会社グリーンセイジュ; 小鍋壽男
Priority date: 1998-01-05
Filing date: 1998-01-05
Publication date: 2004-12-22
Anticipated expiration: 2018-01-05
Also published as: JPH11192497A

Description

【０００１】
【産業上の利用分野】
本発明は微生物の働きを用い排水を中水もしくは浄水レベルにまで処理する廃水処理装置に関する。
【０００２】
【従来の技術】
従来活性汚泥法は、廃水を曝気によって空気を送り溶存酸素を増やし好気性菌の活性化を計ろうとした。水の溶存酸素含有率は温度によって多少変化するが、含有率の上限は２０％である。これまでの活性汚泥法では曝気によって送る空気量を増やせば、増やすほど泡が多くなり泡が廃水処理槽を溢れ出すなどの事態となり、このコントロールが大変難しかった。
【０００３】
たとえば、廃水原水は微生物にとって餌となるが、原水の濃度が濃いときには微生物が消費する酸素量も増えるため、送り込む空気量を多くしなければならないが、処理が進み原水濃度が薄くなると微生物も減るため消費する酸素量も減ることになり、送り込む空気量も少なくてすむ。これに温度のファクタが入ってくるため、曝気によって送り込む空気量のコントロールは極めて難しかった。
【０００４】
そのため、曝気によって空気を送り込み、水の溶存酸素含有率の上限まで酸素含有率を上げようとしても、実際は作り出される泡のために上限まで含有させることができなかった。
【０００５】
【発明が解決しようとする課題】
そこで本発明では、泡の発生を抑え、溶存酸素含有率の上限まで酸素含有率を高め、好気性微生物の働きを最大に引き出しうる廃水処理装置を考えた。
【０００６】
【課題を解決するための技術】
本発明では溶存酸素含有率を高める方法として、曝気による方法だけでなく廃水を空気に接触させつつ流す方法を兼用することを考えた。
【０００７】
具体的には廃水処理槽の処理液面の上方に廃水の排出口を設け、該排出口から排出される廃水を板状部材の上を流下させ、流下過程で接触している空気を取り込み、溶存酸素含有率を高めるようにした。
【０００８】
また、その一方でこの流下させた廃水を前記処理液面に浮上した泡の上に流れ落ちるようにし、消泡の役割も行うように構成した。
【０００９】
【発明の具体的な実施例】
以下本発明に基づき、図面によって具体的に説明する。図１は本発明による微生物を利用する廃水処理装置の第一曝気槽（１）の実施例である。（２）は曝気槽の槽壁、（４）は曝気口、（６）はポンプ、（８）は切り替え弁（１０）は陣笠形状の板状部材、（１２）は原水槽から送られてくる原水、（１４）は第二曝気槽から返送される廃水、（１６）は廃水液面である。
【００１０】
第一曝気槽（１）には、原水槽から廃水原水（１２）が送られ、処理した廃水はポンプ（６）によって切り替え弁（８）を通り、第二曝気槽（２０）に送られ廃水液面（１６）はほぼ一定に保たれている。通常は切り替え弁（８）でパイプライン（２２）を通り、陣笠形状の板状部材の突起部の上方に口をもつ排出口（２４）からポンプ（６）で汲み上げられた廃水が吐出される。
【００１１】
排出口（２４）から吐出された廃水は、液面（１６）に略４５゜の傾斜角をもって作られた板状部材（１０）の表面を略均一に液面（１６）に向かって流れ落ちる。この場合の傾斜角はもちろん４５゜でなくてもよい。曝気槽の大きさ、パイプライン（２２）の口径、ポンプ（６）で送る量などが関係関数として、最適傾斜角を決めることになる。
【００１２】
この陣笠形状の板状部材（１０）の表面を廃水が流れ落ちながら、廃水は接触する空気を取り込み溶存酸素を増やすことになる。これは曝気による方法ではなく溶存酸素を増やす方法で本願の最大の特徴である。もし、処理をしなければならない廃水の処理時間に余裕があれば、曝気による方法をとらず酸素を送り、好気性微生物の活性化を計ることもできる。
【００１３】
最短処理時間で処理しようと思えば、本願のように曝気処理と併用するのがベターである。廃水が陣笠形状の板状部材（１０）の表面を流れ落ちる一方で、曝気口（４）から吹き出される空気によって廃水の曝気が行われ、作られる泡（１８）は液面（１６）上方に図のように溜まって行く。陣笠（１０）に覆われた部分は、その内側にどんどん溜まり、陣笠形状の板状部材（１０）が固定されているため、液面に対し一定の圧力がかかり、浮上してたくる泡を抑える働きをする。
【００１４】
陣笠（１０）に覆われていない部分（２６）（２８）からは、もちろん泡が浮上しそこから槽壁（２）を溢れ出るくらいの泡が吹き出されてくるが、陣笠形状の板状部材（１０）の表面をつたって流れ落ちる廃水がその泡の上に流れ落ち、次から次へと泡を消して行く。そのため通常ならば泡の発生によって曝気する量の制限を受けるが、本願発明による方式をとれば、そうした制限を受けることなく曝気を続けることが出来る。
【００１５】
このように、本願発明による方式は陣笠（１０）を流れ落ちる過程で溶存酸素量を増やすとともに、曝気による溶存酸素量の増加を最大限計ることができ、原水の汚れに対応し、汚れを餌とする微生物に水の溶存酸素含有率の限度まで酸素を送り込むことができ、微生物の活性化を計ることが出来る。
【００１６】
図２は、本願発明による微生物を利用した廃水処理装置の全体構成で、図１と同じ番号は同内容を現す。（３０）は原水槽、（３２）は第二曝気槽、（３４）は一次分離槽、（３６）は第一沈殿槽、（３８）は第二沈殿槽、（４０）は中水貯留槽である。原水槽（３０）の廃水原水はポンプ（４４）によって第一曝気槽（１）に送られ、図１で説明したように微生物の活性化を最大限計り、処理した廃水はポンプ（６）によって切り替え弁（８）を介して、第二曝気槽（３２）に送られる。
【００１７】
第二曝気槽（３２）にも陣笠形状の板状部材（４６）を設けてあり、第一曝気槽（１）と同様の処理が行われる。ここでの処理液は、一次分離槽（３４）にそのまま槽続きで送られ、一次分離槽（３４）では浮上汚泥（４８）と処理液の上澄液に分けられ、上澄液は上方に設けた排出口（５０）より第一分離槽（３６）に送られる。
【００１８】
浮上汚泥（４８）は、ポンプ（５１）によって切り替え弁（５２）を介して、原水槽（３０）ないし第一曝気槽（１）に送られ再処理される。第一沈殿槽（３６）では、間欠曝気によって好気性と嫌気性の微生物を交互に働かせ、一次分離槽（３４）から送られてきた中水をさらに処理し、ポンプ（５４）で第二沈殿槽（３８）に送る。第二沈殿槽（３８）では、静置分離し処理した水はポンプ（５６）で中水貯留槽（４０）に送り、沈殿した汚泥はポンプ（５８）で時々抜き取る。
【００１９】
この全体システムを作動させるに当たり、最初、第一曝気槽（１）に種菌を入れておくが、その菌種をセレクトすると、第二沈殿槽（３８）に沈殿する汚泥の抜き取りは、ほぼゼロとなる。
【００２０】
図３は、本願発明による微生物を利用した廃水処理装置の他の実施例である。この曝気槽（６０）で（６２）は曝気槽の槽壁、（６４）は曝気口、（６６）はポンプ、（６８）は切り替え弁、（７０）はパイプライン、（７２）はその排出口、（７４）は廃水液面、（７６）に対し、略４０゜の傾斜角をもって設置された板状部材である。
【００２１】
図４は、この図３の曝気槽の上面図で、図３のポンプ（６６）によって汲み上げられた廃水は、切り替え弁（６８）を介してパイプライン（７０）に送られ、そこから排出口（７２）にさらに送られ、板状部材（７４）に落下する。
排出口（７２）は、先端に行くに従って大きくなる穴が何カ所かにあけられていて、その穴から落下する液が、板状部材（７４）をほぼ均一に流れ落ちて行くように工夫がなされている。
【００２２】
この図３、図４で説明した曝気槽の場合も、板状部材（７４）の上方に設けられた排出口（７２）から吹き出される廃水が、板状部材（７４）の表面を流れ落ちて行く間に、接触している空気を巻き込んで廃水の溶存酸素を増やすとともに落下する廃水が曝気によって浮上し、板状部材（７４）と槽壁（６２）との間から溢れ出して行こうとする泡を消泡する。
【００２３】
図５は、図１に示した本願発明の曝気槽（１）の上図面であるが、この場合は板状部材（１０）は陣笠状、すなわち円錐状になっているが本願発明は、板状部材がこのような陣笠形状だけでなく、図６のように槽が上方から見たとき正方形の場合、それに合わせて四角錐形状の板状部材（８０）にしてもよいし、図７のように槽が円形の場合でも板状部材を多角錐（８２）にしてもよい。
【００２４】
【発明の効果】
以上説明して来たように、本願発明は空気中の酸素を廃水に取り入れる方法として、曝気による方法だけでなく、廃水液面の上方に設けた板状部材の表面を、廃水を流し落とすことにより接触する空気を取り入れるという方法をとり、且つ、その流下した廃水を、曝気によって生じた泡の消泡に使うという一石二鳥の方法により、溶存酸素含有率も増やすことが出来る。その結果、微生物が必要とする酸素を充分に送ることができ、廃水の処理が飛躍的に進んだ。
【００２５】
実際に、本願発明による第二図に示したような廃水処理装置の実験プラントで牛の糞尿の処理を行ったところ、飲み水にできるくらいまで廃水を浄化処理することができた。
【図面の簡単な説明】
【図１】は本願発明による廃水処理装置の第一曝気槽の概略図、
【図２】は、本願発明による廃水処理装置の全体構成図
【図３】は本願発明による他の曝気槽の概略図
【図４】は図３の上面図、
【図５】は図１の上面図、
【図５】は本願発明による曝気槽と板状部材の上面形状を示す図。
【図６】も本願発明による曝気槽と板状部材の上面形状を示す図。
【図７】も本願発明による曝気槽と板状部材の上面形状を示す図。[0001]
[Industrial applications]
The present invention relates to a wastewater treatment apparatus that treats wastewater to medium water or purified water level using the action of microorganisms.
[0002]
[Prior art]
Conventionally, the activated sludge method attempts to activate aerobic bacteria by increasing the dissolved oxygen by sending air by aeration of wastewater. Although the dissolved oxygen content of water slightly varies depending on the temperature, the upper limit of the content is 20%. In the conventional activated sludge method, if the amount of air sent by aeration was increased, the more the amount of air was increased, the more bubbles were generated, and the bubbles overflowed the wastewater treatment tank. This was very difficult to control.
[0003]
For example, raw wastewater feeds on microorganisms, but when the concentration of raw water is high, the amount of oxygen consumed by the microorganisms also increases, so the amount of air to be sent must be increased, but as the treatment progresses and the concentration of raw water decreases, the number of microorganisms also decreases. As a result, the amount of oxygen consumed is reduced, and the amount of air sent is also reduced. Because of the temperature factor, it was extremely difficult to control the amount of air sent by aeration.
[0004]
Therefore, even if air is supplied by aeration and the oxygen content is increased to the upper limit of the dissolved oxygen content of water, the oxygen content cannot be actually increased to the upper limit due to bubbles produced.
[0005]
[Problems to be solved by the invention]
Therefore, in the present invention, a wastewater treatment apparatus capable of suppressing the generation of bubbles, increasing the oxygen content up to the upper limit of the dissolved oxygen content, and maximizing the action of the aerobic microorganisms was considered.
[0006]
[Technology to solve the problem]
In the present invention, as a method of increasing the dissolved oxygen content, not only the method of aeration but also the method of flowing wastewater while contacting it with air is considered.
[0007]
Specifically, a wastewater discharge port is provided above the treatment liquid level of the wastewater treatment tank, the wastewater discharged from the discharge port flows down on the plate-like member, and takes in the air that is in contact with the flowdown process, The dissolved oxygen content was increased.
[0008]
In addition, on the other hand, the flowed wastewater is made to flow down onto the foam floating on the surface of the treatment liquid, and also serves as a defoamer.
[0009]
Specific Embodiment of the Invention
Hereinafter, the present invention will be specifically described with reference to the drawings. FIG. 1 shows an embodiment of a first aeration tank (1) of a wastewater treatment apparatus using microorganisms according to the present invention. (2) is the tank wall of the aeration tank, (4) is the aeration port, (6) is the pump, (8) is the switching valve (10) is a chinshade-shaped plate member, and (12) is sent from the raw water tank. Coming raw water, (14) is the wastewater returned from the second aeration tank, and (16) is the wastewater level.
[0010]
Raw wastewater (12) is sent from the raw water tank to the first aeration tank (1), and the treated wastewater is sent to the second aeration tank (20) by the pump (6) through the switching valve (8). The liquid level (16) is kept almost constant. Normally, waste water pumped by a pump (6) is discharged from a discharge port (24) having a port above a projection of a jinkasa-shaped plate member through a pipeline (22) by a switching valve (8). .
[0011]
The wastewater discharged from the discharge port (24) flows down the surface of the plate-like member (10), which is formed at an inclination angle of about 45 ° on the liquid surface (16), almost uniformly toward the liquid surface (16). In this case, the inclination angle need not necessarily be 45 °. The size of the aeration tank, the diameter of the pipeline (22), the amount sent by the pump (6), and the like determine the optimum inclination angle as a relational function.
[0012]
While the wastewater flows down on the surface of the chin-shape plate-like member (10), the wastewater takes in the contacting air and increases the dissolved oxygen. This is not the method by aeration but the method of increasing dissolved oxygen, which is the greatest feature of the present application. If there is enough time in the wastewater treatment time to be treated, oxygen can be sent without taking the method by aeration to activate the aerobic microorganisms.
[0013]
If processing is to be performed in the shortest processing time, it is better to use it together with aeration processing as in the present application. While the wastewater flows down the surface of the plat-shaped plate member (10), aeration of the wastewater is performed by air blown out from the aeration port (4), and the foam (18) produced is above the liquid level (16). It accumulates as shown. The portion covered by the jinkasa (10) accumulates more and more inside, and the jinkasa-shaped plate-like member (10) is fixed, so that a constant pressure is applied to the liquid surface, and the rising bubbles are removed. It works to suppress.
[0014]
From the parts (26) and (28) that are not covered by the Jinkasa (10), bubbles of course rise and the bubbles that overflow the tank wall (2) are blown out. The wastewater flowing down the surface of (10) flows down on the foam, and the foam disappears one after another. For this reason, the amount of aeration is usually restricted by the generation of bubbles, but the system according to the present invention can continue the aeration without such restriction.
[0015]
As described above, the method according to the present invention increases the amount of dissolved oxygen in the process of flowing down the jinkasa (10), and can maximize the increase in the amount of dissolved oxygen due to aeration. Oxygen can be fed into the microorganisms to be dissolved to the limit of the dissolved oxygen content of water, and the activation of the microorganisms can be measured.
[0016]
FIG. 2 is an overall configuration of a wastewater treatment apparatus using microorganisms according to the present invention, and the same numbers as those in FIG. 1 indicate the same contents. (30) is a raw water tank, (32) is a second aeration tank, (34) is a primary separation tank, (36) is a first settling tank, (38) is a second settling tank, and (40) is a medium water storage tank. It is. The raw wastewater from the raw water tank (30) is sent to the first aeration tank (1) by a pump (44), and the activation of microorganisms is maximally measured as described in FIG. It is sent to the second aeration tank (32) via the switching valve (8).
[0017]
The second aeration tank (32) is also provided with a chin cap-shaped plate member (46), and the same processing as that of the first aeration tank (1) is performed. The processing liquid here is sent to the primary separation tank (34) as it is, and is separated into a floating sludge (48) and a supernatant of the processing liquid in the primary separation tank (34). It is sent to the first separation tank (36) from the discharge port (50) provided.
[0018]
The floating sludge (48) is sent to the raw water tank (30) or the first aeration tank (1) by the pump (51) via the switching valve (52), and is reprocessed. In the first sedimentation tank (36), aerobic and anaerobic microorganisms are alternately operated by intermittent aeration, and the intermediate water sent from the primary separation tank (34) is further processed, and the second sedimentation is performed by the pump (54). Send to tank (38). In the second sedimentation tank (38), the water separated and treated by standing is sent to the intermediate water storage tank (40) by the pump (56), and the settled sludge is sometimes withdrawn by the pump (58).
[0019]
In order to operate this whole system, seeds are first put in the first aeration tank (1). When the seeds are selected, the sludge settling in the second settling tank (38) is almost zero. Become.
[0020]
FIG. 3 shows another embodiment of the wastewater treatment apparatus using microorganisms according to the present invention. In this aeration tank (60), (62) is the tank wall of the aeration tank, (64) is an aeration port, (66) is a pump, (68) is a switching valve, (70) is a pipeline, and (72) is its drain. The outlet (74) is a plate-like member installed at an inclination angle of about 40 ° with respect to the wastewater level (76).
[0021]
FIG. 4 is a top view of the aeration tank of FIG. 3. The waste water pumped up by the pump (66) of FIG. 3 is sent to a pipeline (70) via a switching valve (68), and the discharge port therefrom. It is further sent to (72) and falls to the plate-like member (74).
The discharge port (72) is provided with several holes which increase in size toward the tip, and is designed so that the liquid falling from the holes flows down the plate member (74) almost uniformly. ing.
[0022]
Also in the case of the aeration tank described with reference to FIGS. 3 and 4, the wastewater blown out from the discharge port (72) provided above the plate member (74) flows down the surface of the plate member (74). While going, entraining the contacting air to increase the dissolved oxygen in the wastewater, and the falling wastewater floats by aeration and tries to overflow from between the plate member (74) and the tank wall (62). Remove foam.
[0023]
FIG. 5 is a top view of the aeration tank (1) of the present invention shown in FIG. 1. In this case, the plate-like member (10) has a skirt shape, that is, a conical shape. When the shape of the tank is not limited to the above-mentioned shape, and the tank is square when viewed from above as shown in FIG. 6, a quadrangular pyramid-shaped plate-like member (80) may be formed in accordance with the square shape. As described above, even when the tank is circular, the plate-shaped member may be a polygonal pyramid (82).
[0024]
【The invention's effect】
As described above, the present invention is not limited to the method of introducing oxygen in the air into the wastewater, not only by aeration, but also by draining the surface of the plate-shaped member provided above the liquid level of the wastewater. The dissolved oxygen content can also be increased by a method of taking in air that comes into contact with the wastewater, and using the wastewater that has flowed down to remove bubbles generated by aeration. As a result, the oxygen required by the microorganisms can be sufficiently supplied, and the treatment of wastewater has progressed dramatically.
[0025]
Actually, when cattle manure was treated in an experimental plant of the wastewater treatment apparatus as shown in FIG. 2 according to the present invention, the wastewater could be purified to the extent that it could be used as drinking water.
[Brief description of the drawings]
FIG. 1 is a schematic view of a first aeration tank of a wastewater treatment apparatus according to the present invention,
FIG. 2 is an overall configuration diagram of a wastewater treatment apparatus according to the present invention. FIG. 3 is a schematic view of another aeration tank according to the present invention. FIG. 4 is a top view of FIG.
FIG. 5 is a top view of FIG. 1,
FIG. 5 is a diagram showing the top shapes of an aeration tank and a plate member according to the present invention.
FIG. 6 is a diagram showing the top shapes of an aeration tank and a plate-like member according to the present invention.
FIG. 7 is a diagram showing the top shapes of an aeration tank and a plate-like member according to the present invention.

Claims

A plate-like member having an internal space in which an upper portion is closed is disposed above the wastewater treatment device, and bubbles generated from an aeration port provided in the wastewater treatment device are captured by the plate-like member. The wastewater is pumped up by a pump installed in the wastewater treatment apparatus, the plate-shaped member is caused to flow down, contact air is entrained in the flow, the amount of dissolved oxygen in the wastewater flowing down is increased, and A wastewater treatment apparatus characterized in that bubbles rising from a gap between the shaped member and the wastewater treatment apparatus are defoamed by the flowing wastewater, and the amount of dissolved oxygen is increased as the treatment time elapses.

The wastewater treatment apparatus according to claim 1, wherein the aeration apparatus is configured to intermittently aerate the anaerobic and aerobic microorganisms alternately to perform wastewater treatment.