JP3974958B2

JP3974958B2 - Oil content processing apparatus and method for treating oil content in waste water

Info

Publication number: JP3974958B2
Application number: JP15323496A
Authority: JP
Inventors: 榮一田代
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-05-23
Filing date: 1996-05-23
Publication date: 2007-09-12
Anticipated expiration: 2016-05-23
Also published as: JPH09314167A

Description

【０００１】
【発明の属する技術分野】
本発明は、厨房排水や食品加工工場等の含油排水中の油分を処理する新規な方法及び装置に関するものである。
【０００２】
【従来の技術】
ホテル、レストラン、大規模食堂、旅館、ゴルフ場、サービスエリア等の厨房排水、或いはガソリンスタンド、機械工場等の排水中には、かなりの量の油分（ノルマルヘキサン抽出物）が含まれている。これらの厨房排水や小規模な食品加工工場等の含油排水は、以前はそのまま放流されることもあったが現在では規制が厳しくなり（排出基準：動植物油は３０ppm 以下、鉱物油は５ppm 以下）、最低でもグリーストラップ（グリス阻集器、グリース捕集器）や夾雑物を分離する滞留装置などの設置が義務付けられるようになってきている。
【０００３】
そして、グリーストラップに溜まった油分はバキュームによる吸引か手作業によって定期的に除去・清掃することになっているが、専門知識をもった人材もいないし付着或いは滞留した油分が酸化・腐敗して強烈な悪臭を発するため、作業員に大きな負担をかけるとともに十分な手入れがなされず、油分が排水とともにそのまま放出されて排水管を目詰まりさせるとか河川を汚染するなど、グリーストラップとして所期の目的を達していないのが現状である。
【０００４】
また、厨房排水の特徴として排水の排出量に時間的なムラがありしかも装置の容量が比較的小さいため、食事時などでは一時に大量の排水が排出され、夜間は逆に長時間滞留するため早朝には悪臭が居間や客席にまで漂う等の難点があった。そこで、グリーストラップの油水分離室（油脂分離槽）内で油分を好気処理（バクテリアの供給と曝気）する試みがなされたが、排水が大量に流された時にバクテリアも一緒に流失してしまい十分な効果が発揮されていない。
【０００５】
この、バクテリアの流失に対処する手段として、１つは、油水分離室或いは油脂分離槽内にバクテリアを供給することが行われている（例えば、特開平７−２８４７９４）。しかし、コストや管理の手間がかかる難点がある。もう１つは、油水分離室或いは油脂分離槽内にバクテリアの担体を配置することが行われている。例えば、特公平７−４７１５６号公報には、グリース捕集槽（１）内の分離油脂層（５）よりも下方に微生物担体収容器（１１）を配置し、更にその下方に曝気用の空気供給具（２２）を設けた技術が示されている（図３参照）。また、特開平７−２４４９６号公報には、油脂分解菌を付着させるパイルを静電植毛したフロッキングバクテリアスクリーン〔１６〕を、油脂分離槽〔１〕内の第２槽〔６〕と第３槽〔７〕内にほぼ垂直に且つ出し入れ自在に設置する技術が示されている（図４参照）。
【０００６】
ところが前者の場合、図３に示すように短期間で微生物担体容器（１１）の周囲にバクテリアコロニーや油脂分など塊Ｃがべったり付着し、処理水が仕切り板（３）の下方から廃水流出室（１ｂ）へ流入するのを妨げる。また、曝気は塊Ｃに妨げられて分離油脂層（５）にまで到達しないので、油脂の分解も進まない。一般に、グリーストラップは小型であり、油脂分離部分は２０〜５０ｃｍ平方、深さも３０〜５０ｃｍ程度である。そのため、容量が小さく未分解の分離油脂層（５）がオーバーフローして排水管から流出するなどの問題を起こす。従って、現状では１週間に１度程度、微生物担体容器（１１）を取り出して掃除するメンテナンスが行われており、その手間と費用は馬鹿にならないものである。尚、図３（ａ）はグリース捕集槽（１）の断面図、図３（ｂ）は分離油脂層（５）を省略して示す平面図である。
【０００７】
また後者では、図４に示すように短期間にフロッキングバクテリアスクリーン〔１６〕の周囲に前記同様バクテリアコロニーや油脂分などの塊Ｃが付着してスクリーン〔１６〕を閉塞し、廃水の流れを止めてしまう。従って、この場合もこまめにフロッキングバクテリアスクリーン〔１６〕の清掃を行なうことが必要になる。しかも、油脂分の付着が甚だしいので、清掃は極めて困難である。
【０００８】
【発明が解決しようとする課題】
一般に、油分（ノルマルヘキサン抽出物）については本格的な生物処理施設でも完全な処理が難しく、処理時間を長くしたり処理槽を大きくする、或いは前処理で加圧浮上して除去するなどで対処している。従って、簡易な厨房排水処理装置などでは油分の完全な分解処理などははまず不可能である。しかし、グリーストラップ内に付着或いは滞留している油分さえある程度処理できれば、グリーストラップとしての役目は果たせるし、従業員や客を悩ます悪臭も軽減される。
【００１０】
【課題を解決するための手段】
以上のような現状に鑑み、本発明者は鋭意研究の結果本発明方法及び装置を完成させたものであり、その特徴とするところは、排水を受水する槽における油水分離室の内側の一部又全体の表面積を大きくしてバクテリアの付着やバクテリアコロニーの付着及び増大化を容易にするととに、油水分離室内で曝気して油脂分の好気分解を促進させるものである。このようにすると、排水が一時に大量に流入してもバクテリアが全部流出することは防がれる。また、油水分離室の中央部や通水路が、バクテリアコロニーによって閉塞されないので、排水の流れを堰止めることもないし曝気が不十分になることもない。しかも、この壁面にオイル吸着性能を有する織物等を取り付けて表面積を大きくすれば、排水中の油脂分が壁面に吸着されるとともに織物等に巣くっているバクテリアにより分解される。更に、排水中や油水分離室等にサポニン含有剤を添加すれば、バクテリアの増殖や分解能の向上が図られる。
【００１１】
ここで本発明が対象とする排水とは、ホテルやレストラン、大規模食堂、旅館、ゴルフ場、サービスエリア等数十〜数百人規模の食事を賄う施設の厨房排水の他、小規模な食品加工工場から排出される含油排水、更には下水設備のない地域での各家庭からの雑排水やガソリンスタンド、小規模な機械工場等からの排水も含まれる。これらの排水は量が比較的少ないが排出源は極めて多く、トータル排水量中に含まれる油分（主として動植物油）の量は無視できないものである。
【００１２】
従って、本発明で言う槽には、単独のグリーストラップや排水の分離・沈澱・滞留処理と併用するグリーストラップのほかに、雑排水処理槽などにおいて油分の浮上分離ができる部分を備えたものなども含まれる。そして、油分の分離ができる部分を油水分離室と定義し、該部分の内壁面の表面積を大きくする。なお、これらの槽は従来のものがあれば、該部分の内壁面に表面積を大きくする凹凸状物を取り付けてそのまま使用することもできる。但し、曝気用の空気供給具の組み込みは必要である。尚、槽の大きさは油分の含有量にもよるが、グリーストラップ単独の場合１００食／１日の施設で２００〜２５０ｌ程度もあればよい。また、油水分離室はその半分〜２／３程度の容量でよい。
【００１３】
また本発明の槽には、排水を受け入れる為の受水室、処理済の排水を溜めて排出する処理水室を設ける。受水室には、野菜屑その他の夾雑物を分離するための受カゴを設置できるようにし、この受カゴを定期的（毎日〜数日に１回程度）に取り出して内容物を廃棄して清掃できる構造のものが好ましい。排水は、この受水室から油水分離室へ送られ、ここで油分を浮上分離し、水は隔壁下部の通路から処理水室へ流入し、装置外へ排出される。小型なものでは、受水室と油水分離室を兼用さすとか処理水室が油水分離室を兼ねる等２室タイプのものもあるが、本発明ではこれらも使用できる。
【００１４】
油水分離室の内側表面の表面積の大きくするには、以下のように種々な手段が考えられる。まず、油水分離室部分の側壁自体や、油水分離室と受水室或いは処理水室とを区画分離する仕切り板自体を、波板等の凹凸条板や凹凸プレス板で構成する。特に、油水分離室と受水室との間の仕切り板の場合、浮上した油分が接触しない部分に透孔を設けて表面積の増大を図ってもよい。透孔は、仕切り板に直接設けてもよいし、パンチングメタルや金網物を使用してもよい。或いは、油水分離室の仕切り板や側壁の表面に、多数の突条や凹溝、窪み、突起、ギザギザ等を設けて、表面積を大きくしてもよい。更に、油水分離室の仕切り板や側壁の表面に、波板等の凹凸条板や凹凸プレス板、パンチングメタル、網状物、織物、不織布など表面積を大きくする凹凸状物を接着や埋め込み、引掛けその他の手段で取り付けるようにしてもよい。特に、凹凸状物として吸油布（オイル吸着能を有する織物や不織布）を用いると、バクテリアの担体としての作用に加えて油脂分の吸着を良好に行なうことができる。
【００１５】
本発明の場合も、油水分離室の内壁面には、バクテリアコロニーが成長する。しかし、油水分離室の壁面近傍を除いた部分にはバクテリアコロニーは存在せず、油水分離室における曝気処理が良好に良好に行なわれるので、油分の好気的分解処理はつつがなく行なわれる。もっとも、受水室からの通水路や処理水室への通水路（各仕切り板の下方の隙間）までもがバクテリアコロニーや油脂分などの塊で塞がれると処理に不都合を生じるので、内壁面の表面積増大化は、これらに近い部分はさけることが望ましい。特に、処理水室との通水路が封鎖されると、浮上した油脂分が処理水室に流入して、油脂分がそのまま系外に流出するおそれがあるので、この部分の表面増大化はできれば避けることが望ましい。表面の増大化するにしても、上下方向の中央部の一部に限るようにすることが望ましい。尚、バクテリアコロニーが成長し過ぎるとか、油分の付着が甚だしいような場合には、適宜油水分離室の壁面を清掃するとよい。この場合の清掃の手間は、従来のようにバクテリア担体容器やフロッキングバクテリアスクリーンを装置外に取り出して行なう場合に比べて非常に簡単である。しかも、清掃を怠ったとしても、グリーストラップが目詰まりを起こすような危険性はない。
【００１６】
このように油水分離室の内壁面部分にバクテリアやバクテリアコロニーが付着していると、一時に大量の排水が流れ込んでもバクテリアの一部は残り、続いての曝気により増大と有機物分解を継続する。従って、連続的なバクテリアの供給などコストのかかることは不要になる。尚、このような３室タイプの場合でも処理しきれなかった油分が処理水室に浮くことがある。また、受水室にも油分が浮くことがある。このような場合に対処するために、受水室や処理水室の内壁表面の一部を表面積増大処理を施しておくことも可能である。吸油布取付の場合、特に望ましい。また、曝気処理は受水室や処理水室でも行なうことが望ましい。
【００１７】
ただ、上記装置においても、油水分離室で分離浮上した油分や内壁面に付着した油分を完全に分解除去することはなかなか困難である。そして、これらグリーストラップ内に残留している油分は、酸化・腐敗して悪臭を放つ。本発明では、これら未処理の油分をサポニン含有剤によって更に完全に処理して快適な処理環境を提供せんとするものである。
【００１８】
ここにサポニンとは、植物体に含有される配糖体の一種で、セッケンのように著しくアワ立つコロイド水溶液を作るものの総称であり、多くの植物から見出されている。本発明では用いるサポニンの種類は問わないが、コストや安定供給の点から、植物体中の含有量が多く且つその植物が大量に存在し安定して入手できるものが好ましい。この観点から、キラヤサポニンやユッカ、なぎいかだ、大豆等から得られるサポニンが好ましい。この内特に、南米のチリー、ボリビア、ペルー等に自生するシャボンの木（学名：Quilaia saponaria Mol.バラ科）から抽出したキラヤサポニンが好適である。これは、化１の構造を有するキラヤ酸をアグリコン（配糖体の非糖質部分）とするトリテルペン系の配糖体であり化２で表わされもので、構造及び分析技術が解明されている数少ないサポニンであるし、比較的サポニン含有濃度の高い抽出液が得られることによる。
【化１】

【化２】

【００１９】
サポニン含有剤は、植物体から抽出した抽出液（溶媒を含む）をそのまま用いてもよく、それを精製したもの自体でもよい。抽出の方法は通常の方法でよく、エタノール等の低級アルコール等で抽出できる。更に、精製物や抽出液を粉状、顆粒状、又は錠剤に加工したものも用いられる。
【００２０】
ところで、本発明者はサポニンが汚水の生物学的処理工程に有効であることを見出したが、これはサポニンが配糖体であるため微生物の栄養分となり、酸素含有量が多いこととあいまって微生物の繁殖を助ける結果、処理効率が向上するものと推察されている。そこで、本発明者は本発明においても油水分離室にサポニン含有剤を供給してその状況を数週間にわって観察したところ、油分はオイル吸着体に綺麗に吸着されて油分浮上が見られず、しかも悪臭が大幅に減少する現象が見られた。これは、サポニンが界面活性作用を有するため処理水の表面張力が減少するとともに、油分の分解を促進した結果と考えられる。しかも、夜間から朝方にかけて槽内で停滞している排水中のＢＯＤやＣＯＤ、ＳＳ成分がそれ以前に比べてかなりの減少を見た。
【００２１】
サポニン含有剤の添加量は、排水中の油分の濃度によって異なるが、通常は、排水に対して精製物換算で0.01〜1.0 ppm 程度である。添加する方法は、液の場合には定量ポンプで常時滴下する方法がよく、顆粒等では２〜３回に分けて１日分を添加するのがよい。これらの方法は、ホテルなどの大規模な施設では可能であるが、一般の家庭や小規模な外食産業等の施設では専任の担当者がいるわけではなく、ポンプの手入れや濃度管理等にはなかなか手が回らないのが実情である。しかも、サポニンの濃度が低下すると処理能力が低下して効果が減少するし、必要以上に高くするとコスト増を招き好ましくない。
【００２２】
このような場合には、サポニン含有剤を徐放性の固形剤とし、これを油水分離室や受水室に適宜個数投入したり、オイル吸着体中に収納しておくようにするとよい。徐放性の固形剤としては、例えば水中で徐々に溶解するワックス、セメント等の基剤とサポニンの抽出液や精製物を混合して固形化したものなどが考えられる。これを、固形剤の溶解の程度を勘案して適宜の日数をおいて適宜個数を投入すると、手間もかからず適切なサポニン濃度の保持が容易に行なえる利点がある。
【００２３】
尚、曝気は排水を攪拌し、油分の浮上や乳化を助けたり油分分解バクテリアの繁殖を助ける。バクテリアは、グリーストラップに使用できるものであれば種類は問わないが、できれば優れた油分分解能を有するように馴致したものが好ましい。これらの細菌が自然発生しないようであれば、別途培養したものを積極的に導入するようにしてもよい。
【００２４】
【発明の実施の形態】
次に、本発明を図面に基づいて詳細に説明する。図１（ａ）は、本発明に係るグリーストラップの一例を示す概略縦断面図、図１（ｂ）は同じく平面図である。このグリーストラップ１は、仕切り板２及び仕切り板３によって、受水室４と油水分離室５及び処理水室６に区画されており、各仕切り板２、３の下方の隙間が通水路７、８になっている。そして、厨房からの排水Ａは流入口９を通ってグリーストラップ１の受水室４に導入され、ここで野菜屑等が受カゴ１０で分離される。次いで、排水は順次油水分離室５に到り、ここで水中の油分が分離浮上する。そして、処理された処理水Ｂは、通水８を通って処理水室６に送られ、排出口１１からグリストラップ１の外に排出される。
【００２５】
油水分離室５の左右の側壁５１、５２には、通水路７、８から上側の部分に波板１２が固着されている。また、仕切り板３は平板状のものであるが、仕切り板２自体も波板で構成されている。従って、油水分離室５は三方の内壁面の表面積が通常のものと比べて大きく、この内壁面特に凹溝部にバクテリアやバクテリアコロニーの付着が生じやすい。また、油分も付着し易い。符号Ｃが、バクテリアコロニーや油分の塊である。そして、油水分離室５の底部に設けた曝気装置（図示略）の空気供給具１３からエアが供給され、油分の分散や排水の好気的な生物処理が行なわれる。尚、受水室４や処理水室６にも空気供給具１４、１５を設けておくとよい。
【００２６】
特に、油水分離室５或いはそれよりも前の段階（受水室４、厨房等）で、排水中にサポニン含有剤を添加すると、サポニンの界面活性作用により油水分離室５内で浮上したり壁面に付着したり或いは排水中に混入している油分が乳化分散し、バクテリアの分解作用を受けやすくなる。このサポニン含有剤は液状のものを定量注入してもよいが、図に示すように錠剤１６に成形したものを、油水分離室５や受水室４内に適宜投入すると、取扱が便利である。
【００２７】
次に、図２は、油水分離室５の内壁面構造が異なる他のグリーストラップ１７を示す。このグリーストラップ１７は、油水分離室５の三方の内壁面の通水路７、８から上側の部分に、吸油布１８を貼着したものである。吸油布１とは、オイル吸着能を有する繊維からなる織物や不織布、或いは織物や不織布にオイル吸着処理を施したものを言う。他は前記例と同じである。この場合、織物や不織布自体が油水分離室内壁面の表面積を増大させてバクテリアやバクテリアコロニーの付着を助けるとともに、排水から分離した或いは排水中に混在する油分を吸着して排水を浄化するとともに、油分の分散や分解を促進させる特徴がある。
【００２８】
【発明の効果】
以上、詳細に説明したように、本発明は排水を受水する槽における油水分離室の内壁の表面積を増大させて、ここにバクテリアコロニーを付着させるとともに、曝気して排水中の油分の分解と除去を行わせるものである。また、サポニン含有剤を排水中に添加するものである。従って、
▲１▼ グリーストラップに、大量の排水が一時に流入してもバクテリアが全て流出することがなく、バクテリアの追加をせずとも排水の好気処理が良好に行なわれる。
▲２▼ バクテリアコロニーによって、油水分離室の中央部や通水路が閉塞されることがないので、処理された或いは処理前の排水の流れが妨げられない。また、曝気による攪拌及び酸素供給が十分に行なわれ、十分な好気処理が担保される。
▲３▼ 油水分離室の手入れは、月に１〜２回程度壁面を清掃する程度でよいので、維持管理が簡単になる。
▲４▼ 特に、サポニン含有剤を添加する場合にあっては、曝気により排水中の油分が綺麗に分散してバクテリアによる分解がし易くなるとともに、平面に付着する油分も完全に処理され、平常時はもとより清掃時にもあまり悪臭を感じず、環境を良好にする。
▲５▼ サポニン含有剤を添加した場合、排出中のノルマルヘキサン抽出物が予想以上に減少し、排水管の詰まり等を防止する。また、ＢＯＤその他の測定値も低下し、排出する排水の水質が良好になる。
【図面の簡単な説明】
【図１】（ａ）は、本発明のグリーストラップの一例を示す概略縦断面図、（ｂ）は同じく平面図である。
【図２】（ａ）は、本発明のグリーストラップの他の例を示す概略縦断面図、（ｂ）は同じく平面図である。
【図３】（ａ）は、従来のグリーストラップの一例を示す概略縦断面図、（ｂ）は分離油脂層を省略した平面図である。
【図４】（ａ）は、従来のグリーストラップの他の例を示す概略縦断面図、（ｂ）は同じく平面図である。
【符号の説明】
１グリーストラップ
２仕切り板
３仕切り板
４受水室
５油水分離室
５１側壁
５２側壁
６処理水室
７通水路
８通水路
１２波板
１３空気供給具
１６錠剤
１７グリーストラップ
１８吸油布
Ｃバクテリアコロニーや油分の塊[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a novel method and apparatus for treating oil in oil-containing wastewater such as kitchen wastewater and food processing plants.
[0002]
[Prior art]
A considerable amount of oil (normal hexane extract) is contained in the kitchen drainage of hotels, restaurants, large-scale dining rooms, inns, golf courses, service areas, etc., or in the drainage of gasoline stations, machine shops, etc. These kitchen wastewater and oil-containing wastewater from small-scale food processing factories were once released as they were before, but now regulations become stricter (emission standards: 30 ppm or less for animal and vegetable oils, 5 ppm or less for mineral oils) At the very least, installation of grease traps (grease interceptors, grease collectors) and retention devices for separating contaminants has become mandatory.
[0003]
The oil collected in the grease trap is regularly removed and cleaned by vacuum suction or manual operation. However, there is no human resource with specialized knowledge, and the adhered or retained oil is oxidized or spoiled. Because it emits a strong foul odor, it puts a heavy burden on workers and is not well cared for, and the intended purpose of the grease trap is to drain the oil as it is with the drainage and clog the drain pipe or pollute the river. It is the present situation that has not been reached.
[0004]
In addition, because of the characteristics of kitchen wastewater, the amount of wastewater discharged is uneven in time and the capacity of the device is relatively small, so a large amount of wastewater is discharged at a time during meals, etc. In the early morning, there were difficulties such as stinking in the living room and audience seats. Therefore, an attempt was made to aerobically treat the oil in the oil trap separation chamber (oil separation tank) (bacteria supply and aeration). However, when a large amount of wastewater was washed away, the bacteria were also washed away. Sufficient effect is not demonstrated.
[0005]
As a means for coping with the loss of bacteria, one is to supply bacteria into an oil / water separation chamber or an oil separation tank (for example, JP-A-7-284794). However, there are drawbacks that require cost and management. The other is to arrange a bacterial carrier in an oil / water separation chamber or oil / fat separation tank. For example, in Japanese Patent Publication No. 7-47156, a microorganism carrier container (11) is disposed below the separated oil and fat layer (5) in the grease collecting tank (1), and aeration air is further provided below the container. The technique provided with the supply tool (22) is shown (refer FIG. 3). Japanese Patent Application Laid-Open No. 7-24496 discloses a flocking bacterial screen [16] electrostatically flocked with a pile to which oil-degrading bacteria are attached, a second tank [6] and a third tank in an oil-separated tank [1]. A technique is shown in which the tank [7] is installed in a substantially vertical manner so as to be freely put in and out (see FIG. 4).
[0006]
However, in the former case, as shown in FIG. 3, a lump C such as bacterial colonies and oils and fats adheres to the periphery of the microorganism carrier container (11) in a short period of time, and the treated water flows from the lower part of the partition plate (3) into the waste water outflow chamber. The flow into (1b) is prevented. Moreover, since aeration is prevented by the lump C and does not reach the separated oil / fat layer (5), the decomposition of the oil / fat does not proceed. In general, the grease trap is small, the oil separation portion is 20 to 50 cm square, and the depth is about 30 to 50 cm. For this reason, there occurs a problem that the undecomposed separated oil / fat layer (5) having a small capacity overflows and flows out of the drain pipe. Therefore, at present, maintenance is performed to take out and clean the microorganism carrier container (11) about once a week, and the labor and cost are not stupid. 3A is a cross-sectional view of the grease collecting tank (1), and FIG. 3B is a plan view in which the separated oil / fat layer (5) is omitted.
[0007]
In the latter case, as shown in FIG. 4, a mass C such as bacterial colonies and oils and fats adheres to the periphery of the flocking bacterial screen [16] in a short period of time to block the screen [16], and the flow of waste water is reduced. I will stop. Therefore, in this case also, it is necessary to frequently clean the flocking bacteria screen [16]. Moreover, since the adhesion of fats and oils is excessive, cleaning is extremely difficult.
[0008]
[Problems to be solved by the invention]
In general, oil (normal hexane extract) is difficult to completely treat even in a full-fledged biological treatment facility, and it can be dealt with by increasing the treatment time, enlarging the treatment tank, or removing it by raising pressure during pretreatment. is doing. Therefore, it is impossible to completely decompose the oil with a simple kitchen wastewater treatment device. However, as long as the oil adhering or staying in the grease trap can be treated to some extent, it can serve as a grease trap, and the bad odor that bothers employees and customers can be reduced.
[0010]
[Means for Solving the Problems]
In view of the present situation as described above, the present inventor has completed the method and apparatus of the present invention as a result of intensive studies. The feature of the present inventor is that it is one of the inside of the oil-water separation chamber in the tank that receives the wastewater. The surface area of the part or the whole is increased to facilitate adhesion of bacteria and bacterial colonies and increase, and aerobic decomposition of fats and oils is promoted by aeration in an oil / water separation chamber. In this way, it is possible to prevent all bacteria from flowing out even if a large amount of wastewater flows in at a time. Moreover, since the central part of the oil-water separation chamber and the water passage are not blocked by the bacterial colonies, the flow of drainage is not blocked and aeration is not insufficient. In addition, if a surface area is increased by attaching a fabric or the like having oil adsorption performance to the wall surface, the oil and fat in the waste water is adsorbed on the wall surface and decomposed by bacteria that are nestled in the fabric and the like. Furthermore, if a saponin-containing agent is added to the waste water or the oil / water separation chamber, bacterial growth and resolution can be improved.
[0011]
Here, the drainage targeted by the present invention is a small-scale food in addition to kitchen drainage of facilities that cover meals of tens to hundreds of people such as hotels, restaurants, large-scale dining rooms, inns, golf courses, service areas, etc. This includes oil-containing wastewater discharged from processing factories, as well as miscellaneous wastewater from households in areas without sewage facilities, wastewater from gasoline stations, and small-scale machine factories. Although the amount of these wastewaters is relatively small, the amount of discharge sources is extremely large, and the amount of oil (mainly animal and vegetable oils) contained in the total amount of wastewater cannot be ignored.
[0012]
Therefore, in the tank referred to in the present invention, in addition to a grease trap used in combination with a single grease trap and wastewater separation / precipitation / stagnation treatment, a tank equipped with a portion capable of floating and separating oil in a miscellaneous wastewater treatment tank, etc. Is also included. And the part which can isolate | separate oil is defined as an oil-water separation chamber, and the surface area of the inner wall surface of this part is enlarged. In addition, if these tanks are conventional, they can be used as they are by attaching irregularities that increase the surface area to the inner wall surface of the tank. However, it is necessary to incorporate an air supply device for aeration. The size of the tank depends on the oil content, but in the case of a grease trap alone, it may be about 200 to 250 l at a facility of 100 meals / day. Further, the oil-water separation chamber may have a capacity of about half to 2/3.
[0013]
The tank of the present invention is provided with a water receiving chamber for receiving waste water and a treatment water chamber for collecting and discharging treated waste water. In the water receiving room, it is possible to install a receiving basket for separating vegetable waste and other foreign matters, and the contents are discarded by taking out the receiving basket regularly (about once every few days). A structure that can be cleaned is preferred. Waste water is sent from the water receiving chamber to the oil / water separation chamber, where the oil is floated and separated, and the water flows into the treated water chamber from the passage under the partition wall and is discharged outside the apparatus. There are two types, such as a water receiving chamber and an oil / water separation chamber, and a treated water chamber also serving as an oil / water separation chamber, but these can also be used in the present invention.
[0014]
In order to increase the surface area of the inner surface of the oil / water separation chamber, various means can be considered as follows. First, the side wall itself of the oil / water separation chamber portion, and the partition plate itself that separates and separates the oil / water separation chamber from the water receiving chamber or the treatment water chamber are formed of concave and convex strips such as corrugated plates and concave and convex press plates. In particular, in the case of the partition plate between the oil / water separation chamber and the water receiving chamber, the surface area may be increased by providing a through hole in a portion where the floating oil component does not contact. The through hole may be provided directly on the partition plate, or a punching metal or a wire netting may be used. Alternatively, the surface area may be increased by providing a large number of ridges, grooves, depressions, protrusions, jagged edges, etc. on the surface of the partition plate or side wall of the oil / water separation chamber. In addition, the surface of the partition wall or side wall of the oil / water separation chamber is bonded, embedded, or hooked with uneven surfaces that increase the surface area such as corrugated plates such as corrugated plates, uneven press plates, punching metal, nets, woven fabrics, and nonwoven fabrics. You may make it attach with another means. In particular, when an oil-absorbing cloth (a woven or non-woven fabric having an oil adsorbing ability) is used as the concavo-convex material, oil and fat can be favorably adsorbed in addition to the action as a bacterial carrier.
[0015]
Also in the present invention, bacterial colonies grow on the inner wall surface of the oil / water separation chamber. However, bacterial colonies do not exist in the portion other than the vicinity of the wall surface of the oil / water separation chamber, and the aeration treatment in the oil / water separation chamber is satisfactorily performed well. However, if the water passage from the water receiving chamber and the water passage to the treatment water chamber (the gap below each partition plate) are blocked by a lump of bacterial colonies or oils and fats, the treatment will be inconvenient. In order to increase the surface area of the wall surface, it is desirable to avoid portions close to these. In particular, if the water passage with the treated water chamber is blocked, the oil and fat that has floated will flow into the treated water chamber, and the oil and fat may flow out of the system as they are. It is desirable to avoid it. Even if the surface is increased, it is desirable to limit it to a part of the central portion in the vertical direction. In addition, when bacterial colonies grow excessively or when the oil content is excessive, the wall surface of the oil / water separation chamber may be appropriately cleaned. The cleaning effort in this case is very simple compared to the case where the bacteria carrier container and the flocking bacteria screen are taken out of the apparatus as in the prior art. Moreover, even if the cleaning is neglected, there is no danger of the grease trap becoming clogged.
[0016]
If bacteria and bacterial colonies adhere to the inner wall surface of the oil / water separation chamber in this way, a part of the bacteria remains even if a large amount of wastewater flows at a time, and the subsequent aeration continues to increase and decompose organic matter. Therefore, it is not necessary to costly supply bacteria continuously. In addition, even in the case of such a three-chamber type, oil that could not be treated may float in the treated water chamber. Oil may also float in the water receiving chamber. In order to cope with such a case, it is also possible to subject the surface of the inner wall of the water receiving chamber or the treatment water chamber to a surface area increasing process. This is particularly desirable when installing an oil absorbent cloth. In addition, it is desirable to perform the aeration process also in the water receiving chamber or the treatment water chamber.
[0017]
However, even in the above apparatus, it is very difficult to completely decompose and remove the oil component separated and floated in the oil-water separation chamber and the oil component adhering to the inner wall surface. The oil remaining in these grease traps oxidizes and rots and gives off a bad odor. In the present invention, these untreated oils are further completely treated with a saponin-containing agent to provide a comfortable treatment environment.
[0018]
Here, saponin is a kind of glycoside contained in a plant body, and is a collective term for making a colloidal aqueous solution that is remarkably abundant like soap, and has been found in many plants. In the present invention, the type of saponin to be used is not limited. From the viewpoint of cost and stable supply, a saponin having a high content in the plant body and a large amount of the plant that can be stably obtained is preferable. From this point of view, saponins obtained from Kiraya saponin, yucca, nagigaida, soybean and the like are preferable. Of these, Quillaja saponin extracted from a soap tree (scientific name: Quilaia saponaria Mol. Rosaceae) that naturally grows in South America such as Chilly, Bolivia, and Peru is preferred. This is a triterpene-based glycoside having aglycone having the structure of Chemical Formula 1 as an aglycon (non-carbohydrate part of the glycoside), and is represented by Chemical Formula 2. This is due to the fact that an extract with a relatively high saponin concentration is obtained.
[Chemical 1]

[Chemical formula 2]

[0019]
As the saponin-containing agent, an extract (including a solvent) extracted from a plant body may be used as it is, or a purified product itself may be used. The extraction method may be a normal method, and can be extracted with a lower alcohol such as ethanol. Further, a refined product or an extract obtained by processing into a powder, granule, or tablet can also be used.
[0020]
By the way, the present inventor has found that saponin is effective in biological treatment processes of sewage, but this is a microorganism, because saponin is a glycoside and has a high oxygen content. It is speculated that the processing efficiency will improve as a result of helping breeding. Therefore, the present inventor also supplied a saponin-containing agent to the oil / water separation chamber in the present invention and observed the situation over several weeks. The oil was adsorbed neatly on the oil adsorbent and no oil floating was observed. Moreover, a phenomenon that the bad odor was greatly reduced was observed. This is considered to be a result of the surface tension of saponin being reduced because the saponin has a surface-active action, and the decomposition of the oil was promoted. In addition, the BOD, COD, and SS components in the wastewater stagnating in the tank from night to morning were significantly reduced compared to before.
[0021]
The amount of saponin-containing agent added varies depending on the oil content in the wastewater, but is usually about 0.01 to 1.0 ppm in terms of purified product relative to the wastewater. In the case of a liquid, the method of addition is preferably a method of constantly dropping with a metering pump, and in the case of granules or the like, it is preferable to add one day in two or three times. These methods can be used in large-scale facilities such as hotels, but there are no dedicated personnel at facilities such as ordinary homes or small-scale restaurants, etc. The fact is that it is hard to turn around. In addition, when the saponin concentration is lowered, the treatment capacity is lowered and the effect is reduced, and when it is higher than necessary, the cost is increased, which is not preferable.
[0022]
In such a case, the saponin-containing agent may be used as a sustained-release solid agent, and an appropriate number of them may be put into an oil / water separation chamber or a water receiving chamber or stored in an oil adsorbent. As the sustained-release solid agent, for example, a solid obtained by mixing a base material such as wax or cement that gradually dissolves in water and an extract or purified product of saponin can be considered. Taking this into account for the degree of dissolution of the solid agent and putting in an appropriate number of days after an appropriate number of days has the advantage that an appropriate saponin concentration can be easily maintained without much trouble.
[0023]
In addition, aeration stirs the wastewater, helps the oil float and emulsify, and helps the oil-degrading bacteria grow. Bacteria may be of any type as long as it can be used in a grease trap, but preferably those adapted to have excellent oil resolution. If these bacteria do not naturally occur, separately cultured ones may be actively introduced.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention will be described in detail with reference to the drawings. FIG. 1A is a schematic longitudinal sectional view showing an example of a grease trap according to the present invention, and FIG. 1B is a plan view of the same. The grease trap 1 is divided into a water receiving chamber 4, an oil / water separation chamber 5, and a treated water chamber 6 by a partition plate 2 and a partition plate 3, and a gap below each

partition plate

2, 3 is a water passage 7, It is eight. Then, the waste water A from the kitchen is introduced into the water receiving chamber 4 of the grease trap 1 through the inflow port 9, where vegetable waste and the like are separated by the receiving basket 10. Subsequently, the waste water sequentially reaches the oil / water separation chamber 5 where the oil in the water separates and floats. Then, the treated water B that has been treated is sent to the treated water chamber 6 through the water flow 8 and is discharged out of the grease strap 1 from the discharge port 11.
[0025]
Corrugated plates 12 are fixed to the left and

right side walls

51, 52 of the oil / water separation chamber 5 in the upper part from the

water flow paths

7, 8. Moreover, although the partition plate 3 is a plate-shaped thing, the partition plate 2 itself is also comprised with the corrugated sheet. Therefore, the oil / water separation chamber 5 has a larger surface area on the inner wall surface of each side than normal ones, and bacteria and bacterial colonies are likely to adhere to the inner wall surface, particularly the groove. Moreover, the oil component is also likely to adhere. Symbol C is a bacterial colony or a lump of oil. And air is supplied from the air supply tool 13 of the aeration apparatus (illustration omitted) provided in the bottom part of the oil-water separation chamber 5, and an aerobic biological treatment of the oil content and drainage is performed.

Air supply tools

14 and 15 may be provided in the water receiving chamber 4 and the treated water chamber 6.
[0026]
In particular, when a saponin-containing agent is added to the drainage in the oil-water separation chamber 5 or in the previous stage (water receiving chamber 4, kitchen, etc.), the surface of the oil-water separation chamber 5 may rise due to the surface active action of the saponin. The oil component adhering to the water or mixed in the wastewater is emulsified and dispersed, and is susceptible to bacterial degradation. This saponin-containing agent may be quantitatively injected as a liquid, but if it is appropriately put into the oil / water separation chamber 5 or the water receiving chamber 4 as shown in the figure, it is convenient to handle. .
[0027]
Next, FIG. 2 shows another grease trap 17 having a different inner wall surface structure of the oil / water separation chamber 5. The grease trap 17 is obtained by adhering an oil absorbing cloth 18 to the upper part from the

water passages

7 and 8 on the inner wall surfaces of the three sides of the oil / water separation chamber 5. The oil-absorbing cloth 1 refers to a woven fabric or a non-woven fabric made of fibers having oil adsorbing ability, or a fabric or non-woven fabric that has been subjected to oil adsorption treatment. Others are the same as the above example. In this case, the woven fabric or non-woven fabric itself increases the surface area of the oil / water separation chamber wall to help adhere bacteria and bacterial colonies, and adsorbs the oil separated from or mixed in the wastewater to purify the wastewater, It has the feature of promoting the dispersion and decomposition of
[0028]
【The invention's effect】
As described above in detail, the present invention increases the surface area of the inner wall of the oil / water separation chamber in the tank that receives the wastewater, attaches bacterial colonies thereto, and aerated to decompose the oil in the wastewater. The removal is performed. Moreover, a saponin-containing agent is added to the waste water. Therefore,
(1) Even if a large amount of wastewater flows into the grease trap at the same time, all the bacteria do not flow out, and the aerobic treatment of the wastewater is performed well without adding bacteria.
(2) Bacterial colonies do not block the central part of the oil-water separation chamber or the water passage, so that the flow of wastewater that has been treated or not treated is not hindered. In addition, agitation and oxygen supply are sufficiently performed, and sufficient aerobic treatment is ensured.
(3) Maintenance of the oil / water separation chamber is simplified because the wall surface only needs to be cleaned once or twice a month.
(4) In particular, when a saponin-containing agent is added, the oil content in the wastewater is neatly dispersed by aeration, and is easily decomposed by bacteria. It doesn't feel bad smell at the time of cleaning.
(5) When a saponin-containing agent is added, the normal hexane extract being discharged is reduced more than expected, and the drainage pipe is prevented from clogging. In addition, BOD and other measured values are also reduced, and the quality of the discharged waste water is improved.
[Brief description of the drawings]
1A is a schematic longitudinal sectional view showing an example of a grease trap according to the present invention, and FIG. 1B is a plan view of the same.
2A is a schematic longitudinal sectional view showing another example of the grease trap of the present invention, and FIG. 2B is a plan view of the same.
3A is a schematic longitudinal sectional view showing an example of a conventional grease trap, and FIG. 3B is a plan view in which a separated oil / fat layer is omitted.
4A is a schematic longitudinal sectional view showing another example of a conventional grease trap, and FIG. 4B is a plan view of the same.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Grease trap 2 Partition plate 3 Partition plate 4 Receiving chamber 5 Oil / water separation chamber 51 Side wall 52 Side wall 6 Treated water chamber 7 Water passage 8 Water passage 12 Corrugated plate 13 Air supply tool 16 Tablet 17 Grease trap 18 Oil absorbing cloth C Lump of oil

Claims

The waste water is received in the water receiving chamber, the oil water is separated in the oil / water separation chamber, and the treated water is stored in the treatment water chamber connected to the oil / water separation chamber via a partition plate open at the bottom. In the oil content processing apparatus that discharges treated water from the chamber, a part or the whole of the inner surface of the wall portion of the oil / water separation chamber excluding the partition plate on the treated water chamber side is configured to have a large surface area and an oil / water separation. An oil processing apparatus comprising an air supply tool for aeration incorporated in a chamber.

The oil content processing apparatus of Claim 1 which comprises the side wall of the oil-water separation chamber except the part of the partition plate by the side of a treated water chamber, or the partition plate itself with the uneven | corrugated plate and corrugated press plate of a corrugated board.

A large number of ridges, grooves, depressions, protrusions, and jagged patterns are provided on the side wall of the oil / water separation chamber excluding the partition plate on the treated water chamber side and the surface of the partition plate. The oil content processing apparatus of Claim 1 which attached the uneven | corrugated shaped object which enlarges a surface area, such as a knitted fabric, a woven fabric, and a nonwoven fabric.

The oil content processing apparatus of Claim 2 or Claim 3 which attaches the textile fabric and nonwoven fabric which have oil adsorption capacity to the side wall of the oil- water separation chamber except the part of the partition plate by the side of a treated water chamber, or the inside of a partition plate.

The waste water is received in the water receiving chamber, the oil water is separated in the oil / water separation chamber, and the treated water is stored in the treatment water chamber connected to the oil / water separation chamber via a partition plate open at the bottom. In an oil content treatment device that discharges treated water from the chamber, the surface of the inside of the wall of the oil / water separation chamber, excluding the partition on the treated water chamber side, is partly or entirely configured to have a large uneven surface area to attach bacterial colonies And a method for treating oil in wastewater, wherein an saponin-containing agent is supplied to an oil separation chamber or an upstream side thereof in an oil treatment apparatus that facilitates the increase.