JP2000024468A - Membrane separation - Google Patents

Membrane separation

Info

Publication number
JP2000024468A
JP2000024468A JP10199169A JP19916998A JP2000024468A JP 2000024468 A JP2000024468 A JP 2000024468A JP 10199169 A JP10199169 A JP 10199169A JP 19916998 A JP19916998 A JP 19916998A JP 2000024468 A JP2000024468 A JP 2000024468A
Authority
JP
Japan
Prior art keywords
water
membrane
treated
fibers
membrane separation
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP10199169A
Other languages
Japanese (ja)
Inventor
Mikio Sato
三生男 佐藤
Masato Noguchi
真人 野口
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sumitomo Heavy Industries Ltd
Original Assignee
Sumitomo Heavy Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sumitomo Heavy Industries Ltd filed Critical Sumitomo Heavy Industries Ltd
Priority to JP10199169A priority Critical patent/JP2000024468A/en
Publication of JP2000024468A publication Critical patent/JP2000024468A/en
Pending legal-status Critical Current

Links

Landscapes

  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a membrane separation method by which a membrane element in a membrane separator is more effectively cleaned and the separator is stably operated for a longer period. SOLUTION: Water 2 to be treated is filter-separated by a membrane element 4 dipped and arranged in the water 2 to be treated in a treating tank 1. In this membrane separation method, the method contains a step in which fibers are added to the water 2 and discreted, and a step in which the element 4 is aerated and cleaned. By such constitution, when the fibers added to the water 2 are discreted in the water 2, the respective disreted fibers are fluidized in the water 2 by the aeration and cleaning, a solid material difficult to fall and deposited on the membrane surface of the element 4 is sufficiently peeled by the respective fibers and the element 4 is effectively cleaned as compared with a conventional membrane separation method in which a suspended solid is charged into the water to be treated.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【発明の属する技術分野】本発明は、処理槽内の被処理
水中に浸漬配置される膜エレメントにより被処理水を膜
分離する膜分離方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a membrane separation method for membrane-separating water to be treated by a membrane element immersed in the water to be treated in a treatment tank.

【０００２】[0002]

【従来の技術】膜分離方法は、処理槽内の被処理水中に
浸漬配置された膜エレメントにより被処理水を膜分離し
てろ過水を得るものである。このような膜分離方法にお
いては、被処理水の種類により活性汚泥のろ過能力が異
なるが、透過流束は、０．４〜０．６ｍ／ｄであること
が一般的である。2. Description of the Related Art In a membrane separation method, water to be treated is subjected to membrane separation by a membrane element immersed in water to be treated in a treatment tank to obtain filtered water. In such a membrane separation method, the filtration capacity of the activated sludge varies depending on the type of the water to be treated, but the permeation flux is generally 0.4 to 0.6 m / d.

【０００３】この場合、必要な膜面積＝処理水量／透過
流束となり、処理水量が大きい場合、大きな膜面積が必
要で、膜分離装置が大型化し、コストが高くなると共に
実用化が困難となる。In this case, required membrane area = processed water amount / permeate flux. When the treated water amount is large, a large membrane area is required, the size of the membrane separation apparatus is increased, the cost is increased, and practical use is difficult. .

【０００４】また、上記膜分離方法においては、ろ過処
理の経過とともに膜のろ過抵抗が徐々に増加し、薬品に
よる洗浄を頻繁に行う必要がある。In the above-mentioned membrane separation method, the filtration resistance of the membrane gradually increases with the lapse of the filtration treatment, and it is necessary to frequently wash the membrane with a chemical.

【０００５】そこで、例えば特開平９−１３６０２１号
公報には、処理水量が大きくなっても膜面積を大きくし
たり薬品洗浄を頻繁に行ったりする必要がないように、
膜エレメントの洗浄を効果的に行い、透過流束を大きく
するようにした方法が開示されている。Therefore, for example, Japanese Patent Application Laid-Open No. Hei 9-136012 discloses that even if the amount of treated water is large, it is not necessary to increase the film area or to frequently perform chemical cleaning.
A method is disclosed in which the cleaning of the membrane element is effectively performed so as to increase the permeation flux.

【０００６】即ち、上記公報には、角状やスポンジ状等
の形状をもった繊維質塊状物等で構成される浮遊固体を
生物反応槽内の被処理水に投入し、この浮遊固体を曝気
により流動させ、曝気による気泡のリフト作用によるせ
ん断力、及び同時に形成される水流によるせん断力に加
え、浮遊固体による膜面に対するせん断力を利用した方
法が開示されている。That is, the above publication discloses that a suspended solid composed of a fibrous mass or the like having a shape such as a square or a sponge is charged into water to be treated in a biological reaction tank, and the suspended solid is aerated. A method is disclosed in which, in addition to a shear force caused by a lift action of bubbles by aeration and a shear force caused by a water stream formed at the same time, a shear force applied to a membrane surface by suspended solids is disclosed.

【０００７】[0007]

【発明が解決しようとする課題】上記公報に記載の膜分
離方法では、膜エレメントの洗浄が効果的に行われ、膜
分離装置の長期安定運転が可能となっている。In the membrane separation method described in the above-mentioned publication, the cleaning of the membrane element is effectively performed, and the long-term stable operation of the membrane separation apparatus becomes possible.

【０００８】しかし、膜分離においては、膜エレメント
の洗浄をより効果的に行い、膜分離装置のより長期間の
安定運転を可能とすることにより、膜分離を効率よく行
うことが望まれている。[0008] However, in membrane separation, it is desired that the membrane element be washed more effectively, and the membrane separation apparatus be operated more stably for a longer period of time, thereby efficiently performing the membrane separation. .

【０００９】そこで、この発明は、上記事情に鑑み、膜
分離装置における膜エレメントの洗浄をより効果的に行
い、膜分離装置のより長期間の安定運転を可能とする膜
分離方法を提供することを目的とする。In view of the above circumstances, the present invention provides a membrane separation method that more effectively cleans a membrane element in a membrane separation device and enables a stable operation of the membrane separation device for a longer period of time. With the goal.

【００１０】[0010]

【課題を解決するための手段】上記目的を達成するた
め、この発明の膜分離方法は、処理槽内の被処理水中に
浸漬配置される膜エレメントにより被処理水を膜分離す
る膜分離方法において、処理槽内の被処理水に繊維を添
加して離散させるステップと、膜エレメントに対して曝
気洗浄を行うステップとを含むことを特徴とする。Means for Solving the Problems To achieve the above object, a membrane separation method according to the present invention is directed to a membrane separation method for membrane-separating water to be treated by a membrane element immersed and disposed in the water to be treated in a treatment tank. And a step of adding fibers to the water to be treated in the treatment tank to separate the water, and performing aeration cleaning of the membrane element.

【００１１】この構成によれば、被処理水に繊維が添加
され、被処理水中で繊維が離散すると、膜エレメントに
対する曝気洗浄により、離散された各繊維が被処理水中
で流動し、各繊維により膜エレメントの膜面に付着した
落ちにくい固形物が十分に剥離され、被処理水に浮遊固
体を投入する従来の膜分離方法に比べて、膜エレメント
の洗浄がより効果的に行われる。According to this structure, when the fibers are added to the water to be treated and the fibers are dispersed in the water to be treated, the separated fibers flow in the water to be treated by aeration and washing of the membrane element, and are separated by the fibers. The hard-to-fall solids adhered to the membrane surface of the membrane element are sufficiently peeled off, and the membrane element is more effectively cleaned as compared with a conventional membrane separation method in which suspended solids are introduced into the water to be treated.

【００１２】上記膜分離方法においては、添加される繊
維は、その平均繊維長さが５０〜５００μｍであるもの
が好ましい。これは、繊維の平均繊維長さが５０μｍ未
満では、離散された各繊維による固形物の剥離効果が低
下する傾向があり、５００μｍを越えると、膜エレメン
トが複数ある場合に、隣接する膜エレメント間に繊維が
詰まることで繊維の流動性が低下し、固形物の剥離効果
が低下する傾向があるからである。In the above membrane separation method, it is preferable that the added fiber has an average fiber length of 50 to 500 μm. This is because if the average fiber length of the fibers is less than 50 μm, the effect of separating solids by the separated fibers tends to decrease, and if it exceeds 500 μm, when there are a plurality of membrane elements, the This is because when the fibers are clogged, the fluidity of the fibers tends to decrease, and the effect of removing solids tends to decrease.

【００１３】また、上記膜分離方法においては、繊維を
含有する繊維含有液中の繊維濃度を被処理水に流入され
るＢＯＤ濃度の１５〜１００％に調整した状態で、繊維
を被処理水に添加することが好ましい。これは、繊維濃
度が流入ＢＯＤ濃度の１５％未満では、膜閉塞が起こっ
て膜面の洗浄効果が低下する傾向があり、一方、繊維濃
度が流入ＢＯＤ濃度の１００％を越えると、膜閉塞は防
止されるものの、処理槽から余剰汚泥が排出される場合
に余剰汚泥の脱水速度が一定となり、繊維を添加しても
その効果が変わらなくなる傾向があるからである。Further, in the above membrane separation method, the fibers are added to the water to be treated while the fiber concentration in the fiber-containing liquid containing the fibers is adjusted to 15 to 100% of the BOD concentration flowing into the water to be treated. It is preferred to add. This is because when the fiber concentration is less than 15% of the inflow BOD concentration, membrane occlusion tends to occur, and the cleaning effect on the membrane surface tends to decrease. On the other hand, when the fiber concentration exceeds 100% of the inflow BOD concentration, the membrane occlusion is reduced. Although it is prevented, when the excess sludge is discharged from the treatment tank, the rate of dehydration of the excess sludge becomes constant, and the effect of adding fibers tends to be unchanged.

【００１４】[0014]

【発明の実施の形態】以下、添付図面と共にこの発明に
よる膜分離方法の好適な実施形態について詳細に説明す
る。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the membrane separation method according to the present invention will be described below in detail with reference to the accompanying drawings.

【００１５】図１は、この発明の膜分離方法を適用する
膜分離装置の一例を示す概略断面図である。図１に示す
ように、膜分離装置１０は処理槽としての生物反応槽１
を備えており、その内部には被処理水（例えば有機排
水）２が浸されている。被処理水２は、被処理水流入ラ
インＬ１を通して供給されるようになっている。被処理
水２には活性汚泥が混入され、余剰汚泥は、生物反応槽
１の底部に取り付けられるラインＬ２を通して排出され
るようになっている。FIG. 1 is a schematic sectional view showing one example of a membrane separation apparatus to which the membrane separation method of the present invention is applied. As shown in FIG. 1, the membrane separation device 10 includes a biological reaction tank 1 as a processing tank.
The treatment water (for example, organic wastewater) 2 is immersed in the inside. The treated water 2 is supplied through a treated water inflow line L1. Activated sludge is mixed in the water 2 to be treated, and excess sludge is discharged through a line L2 attached to the bottom of the biological reaction tank 1.

【００１６】また、被処理水２には、膜モジュールが浸
漬され、この膜モジュールは、複数の膜エレメント４と
しての平膜エレメントを所定間隔離して積層することで
構成されている。また、これらの浸漬膜としては、被処
理水２の水質に応じて、ＵＦ膜又はＭＦ膜のいずれかを
使用することができる。A membrane module is immersed in the water 2 to be treated, and this membrane module is configured by stacking a plurality of flat membrane elements as membrane elements 4 at predetermined intervals. Further, as these immersion films, either the UF film or the MF film can be used depending on the quality of the water 2 to be treated.

【００１７】各膜エレメント４には集水管が接続され、
該各集水管に膜エレメント４の膜を透過した水がろ過水
として集められるようになっている。各集水管はライン
Ｌ３に接続され、該ラインＬ３に接続された吸引ポンプ
Ｐ１によって膜エレメント４内に負圧が発生させられ、
ろ過水が吸引されるようになっている。また、膜エレメ
ント４の下方には、散気ラインＬ４の一端が配設され、
他端は生物反応槽１の外部まで延びている。散気ライン
Ｌ４にはブロア５が取り付けられ、ブロア５によって気
体が散気ラインＬ４を通して被処理水２中に供給され、
曝気が行われ、気泡となって上昇するようになってい
る。気体としては、空気、酸素その他のガスを使用する
ことができる。A water collecting pipe is connected to each membrane element 4,
Water that has passed through the membrane of the membrane element 4 in each of the water collection tubes is collected as filtered water. Each water collecting pipe is connected to a line L3, and a negative pressure is generated in the membrane element 4 by a suction pump P1 connected to the line L3,
The filtered water is sucked. Further, below the membrane element 4, one end of an air diffusion line L4 is provided,
The other end extends to the outside of the biological reaction tank 1. A blower 5 is attached to the air diffusion line L4, and gas is supplied into the water to be treated 2 through the air diffusion line L4 by the blower 5,
Aeration is performed, and the air bubbles rise. As the gas, air, oxygen and other gases can be used.

【００１８】このような膜分離装置１０においては、ブ
ロア５を作動させて膜エレメント４を曝気すると共に吸
引ポンプＰ１を作動させると、曝気による気泡のリフト
作用によるせん断力、及び同時に形成される水流による
せん断力が膜エレメント４の膜表面に加えられることで
膜エレメント４の洗浄が行われ、生物反応槽１内の被処
理水２が膜分離される。In such a membrane separation apparatus 10, when the blower 5 is operated to aerate the membrane element 4 and the suction pump P1 is operated, the shearing force due to the lifting action of the bubbles caused by the aeration and the water flow formed at the same time Is applied to the membrane surface of the membrane element 4, whereby the membrane element 4 is washed, and the water 2 to be treated in the biological reaction tank 1 is subjected to membrane separation.

【００１９】ところで、膜分離装置１０においては、装
置運転時の膜エレメント４の膜の閉塞をより十分防止
し、膜エレメント４の洗浄を効果的に行うことが望まし
い。そこで、本発明者らは、鋭意検討を重ねた結果、被
処理水２に繊維を添加してこれを被処理水２中で離散さ
せることにより膜閉塞の防止、膜エレメント４のより効
果的な洗浄を行うことができることを見い出した。Incidentally, in the membrane separation apparatus 10, it is desirable that the membrane of the membrane element 4 is more sufficiently prevented from being clogged during the operation of the apparatus, and the membrane element 4 is effectively washed. The inventors of the present invention have made intensive studies, and as a result, added fibers to the water to be treated 2 and dispersed the fibers in the water to be treated 2 to prevent membrane blockage and more effectively prevent the membrane element 4 from being added. It has been found that washing can be performed.

【００２０】このため、膜分離装置１０には、繊維を供
給するための繊維供給ラインＬ５が設けられ、この繊維
供給ラインＬ５には、繊維を供給する繊維供給槽６が配
設されている。繊維供給槽６内において、図２に示すよ
うに、繊維７は、水などの液体８中に浸漬され繊維含有
液１３として収容されている。ここで、繊維含有液１３
中の繊維７としては、不溶性を有しかつ汚泥よりも硬い
もの、例えばセルロース繊維が用いられる。繊維７の平
均繊維長さは５０〜５００μｍであることが好ましい。
繊維７の平均繊維長さが５０μｍ未満では、膜エレメン
ト４の膜面の洗浄効果が低下し、膜閉塞を起こす傾向が
あり、平均繊維長さが５００μｍを越えると、隣接する
膜エレメント４間に繊維７が詰まってその流動性が低下
し、膜面の洗浄効果が低下する傾向がある。このような
繊維７は、例えばシート状でかつ繊維質のパルプをシュ
レッダー等を用いて裁断し、更に裁断したパルプを離解
機で離解することで形成される。なお、シート状パルプ
としては、リサイクルの観点から例えば使用済み紙又は
古紙などが好ましい。For this purpose, the membrane separation device 10 is provided with a fiber supply line L5 for supplying fibers, and the fiber supply line L5 is provided with a fiber supply tank 6 for supplying fibers. In the fiber supply tank 6, as shown in FIG. 2, the fibers 7 are immersed in a liquid 8 such as water and stored as a fiber-containing liquid 13. Here, the fiber-containing liquid 13
As the fibers 7 therein, fibers having insolubility and harder than sludge, for example, cellulose fibers are used. The average fiber length of the fibers 7 is preferably 50 to 500 μm.
If the average fiber length of the fibers 7 is less than 50 μm, the cleaning effect on the membrane surface of the membrane element 4 is reduced, and the membrane tends to be clogged. If the average fiber length exceeds 500 μm, the distance between adjacent membrane elements 4 is reduced. The fibers 7 are clogged and their fluidity tends to decrease, and the effect of cleaning the membrane surface tends to decrease. Such fibers 7 are formed, for example, by cutting a sheet-like and fibrous pulp using a shredder or the like, and further disintegrating the cut pulp with a disintegrator. As the sheet pulp, for example, used paper or waste paper is preferable from the viewpoint of recycling.

【００２１】また、被処理水流入ラインＬ１には、その
内部における被処理水２中のＢＯＤ濃度を測定するため
にＢＯＤ濃度計９が取り付けられ、ＢＯＤ濃度計９は、
コントローラ１１を介して繊維供給槽６に接続されてい
る。繊維供給槽６では、繊維濃度は、ＢＯＤ濃度に応じ
て、繊維含有液１３中に所定の濃度に調整されるように
なっている。Further, a BOD concentration meter 9 is attached to the treated water inflow line L1 to measure the BOD concentration in the treated water 2 therein.
It is connected to the fiber supply tank 6 via the controller 11. In the fiber supply tank 6, the fiber concentration is adjusted to a predetermined concentration in the fiber-containing liquid 13 according to the BOD concentration.

【００２２】次に、前述した構成を有する膜分離装置１
０における膜分離方法について説明する。Next, the membrane separation device 1 having the above-described configuration will be described.
The method of membrane separation at 0 will be described.

【００２３】まず、吸引ポンプＰ１により被処理水２を
膜分離しながら、ブロア５を作動させて散気ラインＬ４
を通して膜エレメント４に対して曝気洗浄を行う。この
ようにして、生物反応槽１内の被処理水２中に浸漬配置
された膜エレメント４を曝気して、曝気による気泡１２
のリフト作用によるせん断力、及び同時に形成される水
流Ａによるせん断力を膜エレメント４の膜表面に加え、
膜エレメント４の洗浄を行う。First, while the water to be treated 2 is subjected to membrane separation by the suction pump P1, the blower 5 is operated to set the air diffusion line L4.
Aeration cleaning is performed on the membrane element 4 through the In this way, the membrane element 4 immersed and disposed in the water 2 to be treated in the biological reaction tank 1 is aerated, so that the bubbles 12
The shear force due to the lift action of water and the shear force due to the water flow A formed at the same time are applied to the membrane surface of the membrane element 4,
The membrane element 4 is washed.

【００２４】そして、生物反応槽１内の被処理水２を膜
分離しながら、被処理水流入ラインＬ１を通して被処理
水２を生物反応槽１に投入する。そして、ＢＯＤ濃度計
９によって被処理水流入ラインＬ１の内部における被処
理水２中のＢＯＤ濃度を検出し、このＢＯＤ濃度に応じ
て繊維供給槽６から繊維供給ラインＬ５を通して生物反
応槽１内の被処理水２に添加し、繊維含有液１３中の繊
維７を被処理水２中に離散させる。このとき、繊維含有
液１３中の繊維７の濃度は、被処理水流入ラインＬ１に
おけるＢＯＤ濃度の１５〜１００％となるように調整し
て繊維含有液１３を生物反応槽１内の被処理水２に添加
することが好ましい。これは、繊維７の濃度が、流入Ｂ
ＯＤ濃度の１５％未満では、膜閉塞が起こって膜面の洗
浄効果が低下する傾向があり、一方、繊維濃度が流入Ｂ
ＯＤ濃度の１００％を越えると、膜閉塞は十分防止され
るものの、生物反応槽１から余剰汚泥が排出される場合
に余剰汚泥の脱水速度が一定となり、繊維７の添加によ
る効果が変わらなくなる傾向があるからである。なお、
繊維含有液１３は断続的に、即ち生物反応槽１から余剰
汚泥を引き抜く度ごとに添加される。Then, the water to be treated 2 is introduced into the biological reaction tank 1 through the water to be treated inflow line L1 while the water to be treated 2 in the biological reaction tank 1 is subjected to membrane separation. Then, the BOD concentration meter 9 detects the BOD concentration in the water to be treated 2 inside the water to be treated inflow line L1, and according to the BOD concentration, from the fiber supply tank 6 to the fiber supply line L5 through the fiber supply line L5. The fibers 7 in the fiber-containing liquid 13 are added to the water 2 to be treated and dispersed in the water 2 to be treated. At this time, the concentration of the fiber 7 in the fiber-containing liquid 13 is adjusted so as to be 15 to 100% of the BOD concentration in the water-to-be-treated inflow line L1 so that the fiber-containing liquid 13 is treated with the water to be treated in the biological reaction tank 1. 2 is preferably added. This is because the concentration of fiber 7 is
If the OD concentration is less than 15%, membrane blocking tends to occur and the cleaning effect of the membrane surface tends to decrease, while the fiber concentration decreases
If the OD concentration exceeds 100%, the membrane clogging is sufficiently prevented, but when the excess sludge is discharged from the biological reaction tank 1, the rate of dehydration of the excess sludge becomes constant, and the effect of the addition of the fiber 7 tends not to change. Because there is. In addition,
The fiber-containing liquid 13 is added intermittently, that is, every time excess sludge is withdrawn from the biological reaction tank 1.

【００２５】このようにして繊維７を被処理水２中に離
散させると、膜面近傍にある各繊維７は曝気により上方
に流動され、膜エレメント４の膜面に気泡１２によるせ
ん断力、及び水流Ａによるせん断力のほか、離解された
各繊維７によるせん断力が作用し、この結果、繊維質塊
状物等を被処理水２に添加する従来の膜分離方法に比べ
て、膜エレメント４の膜面に付着した落ちにくい固形物
がより効果的に剥離される。従って、膜分離装置１０に
おける膜閉塞が十分に防止され、ひいては膜分離装置１
０の運転をより長期間安定して継続することができる。When the fibers 7 are dispersed in the water 2 to be treated in this manner, the respective fibers 7 near the membrane surface are caused to flow upward by aeration, so that the shear force of the bubbles 12 on the membrane surface of the membrane element 4 and In addition to the shearing force of the water flow A, the shearing force of each of the disintegrated fibers 7 acts. As a result, compared to the conventional membrane separation method in which fibrous aggregates and the like are added to the water 2 to be treated, the membrane element 4 The hard-to-fall solids adhered to the film surface are more effectively peeled off. Therefore, membrane occlusion in the membrane separation device 10 is sufficiently prevented, and as a result, the membrane separation device 1
0 can be stably continued for a longer period of time.

【００２６】また、膜閉塞が十分防止されるため、膜エ
レメント４のろ過抵抗が小さくなり、膜エレメント４に
おける透過流束を、被処理水２に浮遊固体を投入する従
来の膜分離方法に比べて２０〜３０％高くすることがで
きる。このため、膜エレメント４の膜面積、ひいては膜
分離装置１０を小型化することができる。更に、繊維７
の添加により、余剰汚泥を排出する場合に、繊維７を添
加しない場合に比べて余剰汚泥の脱水速度が向上し、燃
焼処理等に要する経費を低減することができる。Further, since the membrane blockage is sufficiently prevented, the filtration resistance of the membrane element 4 is reduced, and the permeation flux in the membrane element 4 is reduced as compared with the conventional membrane separation method in which suspended solids are introduced into the water 2 to be treated. 20-30% higher. For this reason, the membrane area of the membrane element 4 and thus the membrane separation device 10 can be reduced in size. Furthermore, fiber 7
By adding, the excess sludge is drained at a higher rate when the excess sludge is discharged than when the fiber 7 is not added, and the cost required for combustion treatment and the like can be reduced.

【００２７】上記実施形態では、処理槽として、活性汚
泥を含む生物反応槽１を用いた膜分離装置に適用されて
いるが、本発明の膜分離方法は、生物反応槽１以外の他
の処理槽を用いる膜分離装置に適用することも可能であ
る。In the above embodiment, the membrane separation apparatus using the biological reaction tank 1 containing activated sludge as the treatment tank is applied. It is also possible to apply to a membrane separation device using a tank.

【００２８】更に、上記実施形態では、繊維含有液１３
は断続的に添加されているが、連続的に添加されてもよ
い。Further, in the above embodiment, the fiber-containing liquid 13
Is added intermittently, but may be added continuously.

【００２９】以下、本発明の内容を実施例により具体的
に説明する。Hereinafter, the contents of the present invention will be specifically described with reference to examples.

【００３０】[0030]

【実施例】（実施例１）本発明の膜分離方法を膜分離装
置に適用した例を下記に説明する。膜面積が０．８ｍ2
の膜エレメント（０．５ｍ×１．０６ｍ×２（両面））
を各膜間距離を８ｍｍとして４４枚積層した膜モジュー
ル１ヶを、生物反応槽（１．２ｍ（ｗ）×１．２ｍ
（ｌ）×２．８ｍ（ｈ）＝４ｍ3）とする生物反応槽に
浸漬し、有機排水を毎分１５０ｌの割合で生物反応槽に
供給し、透過流束を１．０ｍ／ｄ、曝気量を０．９ｍ3
／ｍ2膜／時、ＭＬＳＳを１５０００ｍｇ／ｌ、ＢＯＤ
負荷を１．０ｋｇ／ｍ3・ｄに設定して膜分離を行っ
た。このとき、有機排水中のＢＯＤ濃度を測定し、平均
繊維長さ１００μｍの繊維を含み且つその繊維濃度がＢ
ＯＤ濃度の３０％である繊維含有液を連続的に添加し
た。ここで、繊維は、不要のコピー再生紙をシュレッダ
ーで３〜５ｍｍに裁断し、高速離解機で平均繊維長さ１
００μｍとしたものである。その結果、図４に示すよう
に、繊維を添加した後、５０日程度まではろ過差圧はほ
とんど増加しなかった。なお、図４において、横軸は膜
分離装置の運転時間、縦軸は２５℃におけるろ過差圧で
ある。(Embodiment 1) An example in which the membrane separation method of the present invention is applied to a membrane separation apparatus will be described below. 0.8m 2 membrane area
(0.5mx 1.06mx 2 (both sides))
Are stacked in a biological reaction tank (1.2 m (w) × 1.2 m) by stacking 44 membrane modules with each membrane distance being 8 mm.
(L) × 2.8 m (h) = 4 m 3 ), immersed in a biological reaction tank, supplied organic wastewater to the biological reaction tank at a rate of 150 l / min, and provided a permeation flux of 1.0 m / d and aeration. 0.9m 3
/ M 2 membrane / h, MLSS at 15000 mg / l, BOD
The load was set to 1.0 kg / m 3 · d to perform membrane separation. At this time, the BOD concentration in the organic waste water was measured, and the fibers containing fibers having an average fiber length of 100 μm and having a fiber concentration of B
A fiber-containing liquid having an OD concentration of 30% was continuously added. Here, the fiber is cut into unnecessary copy recycled paper with a shredder to 3 to 5 mm, and the average fiber length is 1 with a high-speed disintegrator.
The thickness was set to 00 μm. As a result, as shown in FIG. 4, the filtration pressure difference hardly increased until about 50 days after the fiber was added. In FIG. 4, the horizontal axis represents the operation time of the membrane separation device, and the vertical axis represents the filtration pressure difference at 25 ° C.

【００３１】（実施例２）膜閉塞に対する平均繊維長さ
の影響を調べるべく、平均繊維長さを２０〜８００μｍ
にわたって変化させた以外は実施例１における膜分離と
同様の条件で膜分離を行った。その結果を図５に示す。
図５に示すように、平均繊維長さが５０μｍ未満になる
と、ろ過差圧が大きく増加した。一方、５０μｍ以上で
は、ろ過差圧は１０ｋＰａとなったが、５００μｍを越
えるとろ過差圧が徐々に増加し始めた。そして、７００
μｍになったときにはろ過差圧はあまり増加しなかった
ものの、流路閉塞が認められた。Example 2 In order to examine the effect of the average fiber length on membrane occlusion, the average fiber length was set to 20 to 800 μm.
The membrane separation was performed under the same conditions as in the membrane separation in Example 1 except that the temperature was changed over the range. The result is shown in FIG.
As shown in FIG. 5, when the average fiber length was less than 50 μm, the filtration pressure difference increased significantly. On the other hand, at 50 μm or more, the filtration pressure difference was 10 kPa, but when it exceeded 500 μm, the filtration pressure difference began to gradually increase. And 700
Although the filtration pressure difference did not increase so much when it became μm, the flow path was blocked.

【００３２】以上のことから、繊維の平均繊維長さは、
５０〜５００μｍであることが適当であることが分かっ
た。From the above, the average fiber length of the fiber is:
It has been found that a thickness of 50 to 500 μm is appropriate.

【００３３】（実施例３）膜閉塞に対する繊維濃度の影
響と、余剰汚泥の脱水速度に対する繊維濃度の影響とを
調べるべく、以下のことを行った。Example 3 In order to examine the effect of the fiber concentration on the membrane blockage and the effect of the fiber concentration on the dewatering speed of the excess sludge, the following was performed.

【００３４】即ち、まず、繊維濃度を流入ＢＯＤ濃度の
５〜１３０％にわたって変化させた以外は、実施例１に
おける膜分離と同様の条件で膜分離を行った。その結果
を図６に示す。図６に示すように、繊維濃度が流入ＢＯ
Ｄ濃度の１５％未満では、ろ過差圧が大きくなったもの
の、繊維濃度が１５％以上ではろ過差圧は一定であっ
た。That is, first, membrane separation was performed under the same conditions as those in Example 1 except that the fiber concentration was changed from 5 to 130% of the inflow BOD concentration. FIG. 6 shows the result. As shown in FIG.
When the D concentration was less than 15%, the filtration pressure difference increased, but when the fiber concentration was 15% or more, the filtration pressure difference was constant.

【００３５】一方、実施例１における膜分離と同様の条
件で膜分離を行い、膜分離にあたって流入ＢＯＤ濃度の
０〜１３０％だけ繊維濃度を変化させ、膜分離装置から
排出された余剰汚泥について脱水速度を調べた。その結
果を図７に示す。図７に示すように、繊維濃度が１００
％を越えると、脱水速度はほぼ一定となった。On the other hand, membrane separation is carried out under the same conditions as in the membrane separation in Example 1, the fiber concentration is changed by 0 to 130% of the inflow BOD concentration in the membrane separation, and excess sludge discharged from the membrane separation device is dewatered. I checked the speed. FIG. 7 shows the result. As shown in FIG.
%, The dehydration rate became almost constant.

【００３６】以上のことから、繊維濃度は流入ＢＯＤ濃
度の１５〜１００％が適当であることが分かった。From the above, it was found that the fiber concentration was suitably 15 to 100% of the inflow BOD concentration.

【００３７】（比較例１）生物反応槽内の被処理水に繊
維を添加せず透過流束を０．６ｍ／ｄで膜分離を行った
以外は、実施例１と同様にして膜分離を行った。そし
て、膜分離装置作動開始後のろ過差圧の経時変化を測定
した。その結果を図８に示す。図８に示すように、当初
５ｋＰａであったろ過差圧が５０日後には５０ｋＰａま
で上昇し、これ以降の安定処理ができなくなった。Comparative Example 1 Membrane separation was performed in the same manner as in Example 1 except that the fiber was not added to the water to be treated in the biological reaction tank and the permeation flux was 0.6 m / d. went. Then, the change with time of the filtration differential pressure after the operation of the membrane separation device was started was measured. FIG. 8 shows the result. As shown in FIG. 8, the filtration pressure difference, which was initially 5 kPa, increased to 50 kPa after 50 days, and the subsequent stabilization treatment could not be performed.

【００３８】以上のことから、繊維の平均繊維長さは、
５０〜５００μｍであることが適当であることが分かっ
た。From the above, the average fiber length of the fiber is:
It has been found that a thickness of 50 to 500 μm is appropriate.

【００３９】（比較例２）繊維に代えて、比重１．０
１、大きさ３ｍｍのセルロースの角状固体を被処理水に
添加した以外は、実施例１の場合と同様の条件で膜分離
を行った。その結果を図９に示す。図９に示すように、
ろ過差圧が時間とともに増加し、当初５ｋＰａであった
ろ過差圧が５０日後には１２ｋＰａまで上昇した。Comparative Example 2 A specific gravity of 1.0 was used instead of the fiber.
1. Membrane separation was carried out under the same conditions as in Example 1 except that a horny solid of cellulose having a size of 3 mm was added to the water to be treated. FIG. 9 shows the result. As shown in FIG.
The filtration pressure difference increased with time, and the filtration pressure difference, which was initially 5 kPa, increased to 12 kPa after 50 days.

【００４０】[0040]

【発明の効果】以上述べたように、この発明の膜分離方
法によれば、離散された各繊維が膜エレメントの曝気洗
浄により被処理水中で流動し、膜エレメントの膜面に付
着した落ちにくい固形物が十分剥離され、その結果、膜
閉塞のより十分な防止、ひいては膜分離装置のより一層
の長期安定運転を可能とすることができる。As described above, according to the membrane separation method of the present invention, each of the separated fibers flows in the water to be treated by aeration and washing of the membrane element, and is less likely to adhere to the membrane surface of the membrane element. The solids are sufficiently peeled off, and as a result, it is possible to prevent the membrane from being clogged more sufficiently, thereby enabling a longer-term stable operation of the membrane separation device.

【００４１】この発明の膜分離方法は、種々の用途、例
えば産業排水の生物処理、ＣＰ（コミュニティプラン
ト、団地汚水処理施設）の生物処理、浸出水処理、農村
集落排水及び小規模下水の生物処理、その他の有機排水
の脱窒処理を含む生物処理などに適用可能である。The membrane separation method of the present invention can be used for various purposes, for example, biological treatment of industrial wastewater, biological treatment of CP (community plant, complex sewage treatment facility), leachate treatment, rural settlement wastewater and small-scale sewage treatment. The present invention is applicable to biological treatment including denitrification treatment of other organic wastewater.

【図面の簡単な説明】[Brief description of the drawings]

【図１】本発明の膜分離方法を適用する膜分離装置の一
例を示す断面図である。FIG. 1 is a cross-sectional view showing one example of a membrane separation apparatus to which a membrane separation method of the present invention is applied.

【図２】繊維含有液中の繊維を示す概略図である。FIG. 2 is a schematic diagram showing fibers in a fiber-containing liquid.

【図３】膜エレメントの近傍における繊維の流動状態を
示す概略図である。FIG. 3 is a schematic diagram showing a flow state of fibers in the vicinity of a membrane element.

【図４】実施例１の膜分離方法によるろ過差圧の経時変
化を示すグラフである。FIG. 4 is a graph showing a change with time of a filtration pressure difference according to the membrane separation method of Example 1.

【図５】実施例２における繊維の平均繊維長さに対する
ろ過差圧の関係を示すグラフである。FIG. 5 is a graph showing the relationship between the average fiber length of the fibers and the filtration pressure difference in Example 2.

【図６】実施例３における繊維濃度割合に対するろ過差
圧の関係を示すグラフである。FIG. 6 is a graph showing the relationship between the fiber concentration ratio and the filtration pressure difference in Example 3.

【図７】実施例３における繊維濃度割合に対する余剰汚
泥の脱水速度の関係を示すグラフである。FIG. 7 is a graph showing a relationship between a fiber concentration ratio and a dewatering speed of excess sludge in Example 3.

【図８】比較例１の膜分離方法によるろ過差圧の経時変
化を示すグラフである。FIG. 8 is a graph showing the change over time of the filtration pressure difference according to the membrane separation method of Comparative Example 1.

【図９】比較例２の膜分離方法によるろ過差圧の経時変
化を示すグラフである。FIG. 9 is a graph showing the change over time of the filtration pressure difference by the membrane separation method of Comparative Example 2.

【符号の説明】[Explanation of symbols]

１…生物反応槽（処理槽）、２…被処理水、４…膜エレ
メント、７…繊維、９…繊維含有液、１０…膜分離装
置。DESCRIPTION OF SYMBOLS 1 ... Biological reaction tank (treatment tank), 2 ... Water to be treated, 4 ... Membrane element, 7 ... Fiber, 9 ... Fiber-containing liquid, 10 ... Membrane separation device.

フロントページの続き Ｆターム(参考） 4D006 GA06 GA07 HA42 HA93 JA31Z JA36A JA36B JA36C KA03 KA33 KA43 KA44 KC02 KC14 KC17 KC20 KD30 KE12P PA01 PB08 PB24 PC61 Continued on the front page F term (reference) 4D006 GA06 GA07 HA42 HA93 JA31Z JA36A JA36B JA36C KA03 KA33 KA43 KA44 KC02 KC14 KC17 KC20 KD30 KE12P PA01 PB08 PB24 PC61

Claims (5)

【特許請求の範囲】[Claims] 【請求項１】 処理槽内の被処理水中に浸漬配置される
膜エレメントにより前記被処理水を膜分離する膜分離方
法において、 前記処理槽内の前記被処理水に繊維を添加して離散させ
るステップと、 前記膜エレメントに対して曝気洗浄を行うステップと、
を含むことを特徴とする膜分離方法。1. A membrane separation method for membrane-separating said water to be treated by a membrane element immersed and disposed in the water to be treated in a treatment tank, wherein fibers are added to said water to be treated in said treatment tank and dispersed. Performing aeration cleaning on the membrane element;
A membrane separation method comprising: 【請求項２】 前記繊維の平均繊維長さが５０〜５００
μｍであることを特徴とする請求項１に記載の膜分離方
法。2. The fiber according to claim 1, wherein the average fiber length is 50 to 500.
2. The method according to claim 1, wherein the thickness is μm. 【請求項３】 前記繊維を含有する繊維含有液中の繊維
濃度を前記被処理水に流入されるＢＯＤ濃度の１５〜１
００％に調整した状態で、前記繊維を前記被処理水に添
加することを特徴とする請求項１又は２に記載の膜分離
方法。3. The fiber concentration in the fiber-containing liquid containing the fibers is adjusted to a BOD concentration of 15 to 1 which is introduced into the water to be treated.
The method according to claim 1, wherein the fiber is added to the water to be treated in a state where the water is adjusted to 00%. 【請求項４】 前記繊維がセルロース繊維であることを
特徴とする請求項１〜３のいずれか一項に記載の膜分離
方法。4. The method according to claim 1, wherein the fibers are cellulose fibers. 【請求項５】 前記繊維が、シート状パルプを裁断した
後に離解することにより作られることを特徴とする請求
項１〜４のいずれか一項に記載の膜分離方法。5. The membrane separation method according to claim 1, wherein the fibers are produced by cutting and defibrating the sheet pulp.
JP10199169A 1998-07-14 1998-07-14 Membrane separation Pending JP2000024468A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10199169A JP2000024468A (en) 1998-07-14 1998-07-14 Membrane separation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10199169A JP2000024468A (en) 1998-07-14 1998-07-14 Membrane separation

Publications (1)

Publication Number Publication Date
JP2000024468A true JP2000024468A (en) 2000-01-25

Family

ID=16403311

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10199169A Pending JP2000024468A (en) 1998-07-14 1998-07-14 Membrane separation

Country Status (1)

Country Link
JP (1) JP2000024468A (en)

Similar Documents

Publication Publication Date Title
JP2008229628A (en) Water treatment apparatus and water treatment method
WO2001072643A1 (en) Method and apparatus for treating waste water
JP5850793B2 (en) Suspended water filtration apparatus and method
JPH11309480A (en) Operating method of immersion type membrane separation device
JP5586749B2 (en) Membrane separation activated sludge treatment apparatus and membrane separation activated sludge treatment method
JP3491122B2 (en) Water treatment equipment
JP2009247936A (en) Method of inline-cleaning immersion type membrane-separation device
WO2008035710A1 (en) Method of wastewater disposal
CN215049321U (en) Advanced oxidation reaction system for wastewater treatment
JP2000024468A (en) Membrane separation
JP2006289152A (en) Method of treating organic waste water and apparatus thereof
JP3773360B2 (en) Septic tank with membrane separation
JPH04215811A (en) Treatment apparatus for separating at least artificial and natural fibers in night soil or sewage water
JP4335193B2 (en) Method and apparatus for treating organic wastewater
JP4124957B2 (en) Filter body washing method and apparatus
JP3563319B2 (en) Yeast reactor with screen-type solid-liquid separator
JP2000084554A (en) Method for operating water treating apparatus having membrane separator
JP3162339B2 (en) Sludge treatment method and treatment system
JPH10202010A (en) Water treatment device
JP2002320828A (en) Filter membrane system solid-liquid separator and waste water treatment equipment with the same
JPH09267097A (en) Combination treatment septic device
JP2004261663A (en) Treatment method for organic wastewater
JP2938442B1 (en) Sludge treatment method and treatment system
JP2000140879A (en) Activated sludge method
JP2000279984A (en) Biological treatment equipment