JP7498888B2 - Filtration method - Google Patents

Filtration method Download PDF

Info

Publication number
JP7498888B2
JP7498888B2 JP2021136793A JP2021136793A JP7498888B2 JP 7498888 B2 JP7498888 B2 JP 7498888B2 JP 2021136793 A JP2021136793 A JP 2021136793A JP 2021136793 A JP2021136793 A JP 2021136793A JP 7498888 B2 JP7498888 B2 JP 7498888B2
Authority
JP
Japan
Prior art keywords
filtration
filter
layer
filter medium
return prevention
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.)
Active
Application number
JP2021136793A
Other languages
Japanese (ja)
Other versions
JP2023031356A (en
Inventor
仁貴 富澤
雅義 片山
秀隆 氏家
優 西山
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.)
Ishigaki Co Ltd
Original Assignee
Ishigaki Co 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 Ishigaki Co Ltd filed Critical Ishigaki Co Ltd
Priority to JP2021136793A priority Critical patent/JP7498888B2/en
Publication of JP2023031356A publication Critical patent/JP2023031356A/en
Application granted granted Critical
Publication of JP7498888B2 publication Critical patent/JP7498888B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/10—Biological treatment of water, waste water, or sewage

Landscapes

  • Filtration Of Liquid (AREA)

Description

本発明は、粒状繊維ろ材を用いて被処理液のろ過を行う下向流式ろ過装置に関し、ろ過処理工程前段でろ材層を圧密させ、効率よくろ過を行うろ過装置およびろ過処理方法に関する。 The present invention relates to a downflow filtration device that uses granular fiber filter media to filter the liquid being treated, and to a filtration device and filtration method that compacts the filter media layer in the early stages of the filtration process to perform efficient filtration.

従来、沈降性の粒状繊維ろ材を内部に充填したろ過装置の上部から被処理液を供給して、被処理液中の夾雑物を除去するろ過処理方法が知られている。このろ過処理方法において、ろ過槽内に形成されたろ材層の空隙率が高い場合、被処理液中の夾雑物の粒子径が小さいと被処理液がろ材間を通過しやすくなり、被処理液中の夾雑物がろ材層で十分に捕捉されない。そのため、ろ過処理工程の前段でろ材層を圧密して層内の空隙率を低くし、ろ過能力を高める必要があった。 Conventionally, a filtration method is known in which the liquid to be treated is supplied from the top of a filtration device filled with sedimentary granular fiber filter media to remove impurities from the liquid to be treated. In this filtration method, if the porosity of the filter media layer formed in the filtration tank is high, the liquid to be treated will easily pass through the filter media if the particle size of the impurities in the liquid to be treated is small, and the impurities in the liquid to be treated will not be sufficiently captured by the filter media layer. For this reason, it was necessary to consolidate the filter media layer in the early stages of the filtration process to reduce the porosity within the layer and increase the filtration capacity.

特許文献１には、濾過工程の前段で濾過装置に供給した洗浄用水を濾過装置底部より排水させて濾層を濾過装置下部に圧縮させる技術が開示されている。 Patent document 1 discloses a technology in which the cleaning water supplied to the filtration device in the first stage of the filtration process is drained from the bottom of the filtration device, compressing the filter layer to the bottom of the filtration device.

また、特許文献２には繊維ろ材層の一方に原水が流通可能で繊維ろ材の流出を防止するメッシュが張設された通水孔を有するろ材操作部材を備えたろ過装置が開示されている。このろ過装置は、ろ材支持部材側から供給する原水の流れの圧力によって繊維ろ材をろ材支持部材側へ摺動させ、繊維ろ材をろ材支持部材との間に挟みつけて圧縮した状態でろ過操作を行っている。 Patent Document 2 also discloses a filtration device equipped with a filter medium operating member having a water passage hole on one side of the fibrous filter medium layer through which raw water can flow and which is fitted with a mesh that prevents the fibrous filter medium from flowing out. In this filtration device, the fibrous filter medium is slid toward the filter medium support member side by the pressure of the flow of raw water supplied from the filter medium support member side, and the filtration operation is performed in a state in which the fibrous filter medium is sandwiched and compressed between the filter medium support member and the filter medium.

特開平９－２３４３０９号公報Japanese Patent Application Laid-Open No. 9-234309 特許第４４７５９２４号公報Patent No. 4475924

従来のろ過処理方法では、ろ過装置内に積層された粒状繊維ろ材同士が十分に圧密していないため、ろ材層の空隙率が高くなっている。これに伴い、上部より供給された被処理液に微小な粒子の割合が多く含まれていた場合には、含有する夾雑物がろ材層で十分に捕捉されないまま下部より排出されるため、ろ過精度を高めることができなかった。 In conventional filtration methods, the granular fiber filter media stacked inside the filtration device are not sufficiently compressed together, resulting in a high porosity in the filter media layer. As a result, if the treated liquid supplied from the top contains a high proportion of fine particles, the impurities contained in the liquid are discharged from the bottom without being sufficiently captured by the filter media layer, making it impossible to improve filtration accuracy.

特許文献１では一時的に濾層を濾過装置下部に圧縮させることは可能であるが、濾過工程に移行する際あるいは濾過工程中に、濾層に作用する圧力が前記圧縮圧力以下となると、特に開放面近傍の濾層が緩んで上方に展開され、均一な圧密が維持できないことがある。被処理液は空隙率の高い濾層上部をすり抜けて濾層下部で集中的にろ過されるため、濾層全体を有効活用できず、長時間安定したろ過処理を行うことができないという課題がある。 In Patent Document 1, it is possible to temporarily compress the filter layer to the lower part of the filtration device, but if the pressure acting on the filter layer falls below the compression pressure when transitioning to the filtration process or during the filtration process, the filter layer, particularly near the open surface, may loosen and expand upward, making it impossible to maintain uniform compaction. The liquid to be treated passes through the upper part of the filter layer, which has a high porosity, and is filtered intensively at the lower part of the filter layer, so the entire filter layer cannot be used effectively, and stable filtration cannot be performed for long periods of time.

特許文献２では繊維ろ材を原水により圧縮するため、ろ過処理工程の初期は十分な圧密ができていない状態であり、原水中の懸濁物質がろ材層を通過して処理水とともに排出されるという課題がある。 In Patent Document 2, the fiber filter medium is compressed by the raw water, so there is an issue that sufficient compression is not achieved at the beginning of the filtration process, and suspended solids in the raw water pass through the filter medium layer and are discharged together with the treated water.

また、本出願人の実験により、押圧部材により繊維ろ材層を一方から押圧した場合、ろ材同士やろ材槽との摩擦力等によりろ材層の押圧部材側のみが圧密されることが判明している。特許文献２では繊維ろ材は原水の流れによる圧力で圧縮されるとともに、原水の流れによる圧力を受けたろ材支持部材により一方から押圧されている。しかし、流れによる圧縮作用よりろ材支持部材の面圧による圧縮作用が大きいため、繊維ろ材層ではろ材支持部材側の圧密度が高くなり、均一に圧縮されていないと推測できる。そのため、ろ過処理の早期に目詰まりが発生する可能性がある。 Furthermore, the applicant's experiments have revealed that when the fibrous filter layer is pressed from one side by a pressing member, only the pressing member side of the filter layer is compressed due to friction between the filter media and between the filter media and the filter media tank. In Patent Document 2, the fibrous filter media is compressed by the pressure of the raw water flow, and is pressed from one side by the filter media support member which is subjected to the pressure of the raw water flow. However, since the compressive effect due to the surface pressure of the filter media support member is greater than the compressive effect due to the flow, it can be inferred that the degree of compression on the filter media support member side of the fibrous filter layer is higher and not compressed uniformly. As a result, clogging may occur early in the filtration process.

さらに、繊維ろ材の洗浄時には処理水の排出側から供給した洗浄処理液の流れによる圧力でろ材支持部材を原水供給側に移動させている。つまり、ろ材支持部材は原水や洗浄処理液の流れによる圧力で移動自在に構成してあり、位置を固定させる手段を持ち合わせていない。ろ過処理工程で原水の供給圧力に応じてろ材支持部材が移動し、繊維ろ材層の圧密度が変動するため安定したろ過処理を行うことができないという課題がある。 Furthermore, when cleaning the fiber filter media, the filter media support member is moved to the raw water supply side by the pressure caused by the flow of cleaning treatment liquid supplied from the discharge side of the treated water. In other words, the filter media support member is configured to be freely movable by the pressure caused by the flow of raw water and cleaning treatment liquid, and does not have a means to fix its position. There is an issue that the filter media support member moves in response to the raw water supply pressure during the filtration process, causing the compaction density of the fiber filter media layer to fluctuate and making it impossible to perform stable filtration.

本発明はこのような実情に鑑みてなされたもので、粒状繊維ろ材を使用したろ過装置を用いてろ過処理を行う場合に生じる従来の課題をすべて解決し、且つ高精度のろ過処理を長時間安定して行うことができるろ過装置及びろ過処理方法を提供する。 The present invention was made in consideration of these circumstances, and provides a filtration device and a filtration method that solves all of the conventional problems that arise when performing filtration processing using a filtration device that uses granular fiber filter media, and that can perform high-precision filtration processing stably for long periods of time.

本発明は、ろ過処理工程の前段で沈降性の粒状繊維ろ材を圧密するろ過処理方法において、浮力調整機構と空気溜りを有する戻り防止部材を下降させ、圧密工程で圧縮されたろ材層による開放面への戻りが発生する前に、ろ材層表層に戻り防止部材を静置させてろ材層の圧密を維持する戻り防止工程と、ろ過槽に貯留した圧密水を底部から排水し、繊維ろ材を圧縮してろ材層を形成する圧密工程と、を実施した後、ろ過処理工程を開始するもので、ろ材層全体が均一で圧密度が高い安定した状態を形成でき、運転初期から長時間安定して清澄な処理水を得ることができる。また、圧密後のろ材層の緩みを防止した状態でろ過処理運転を開始できる。 The present invention is a filtration method for consolidating a sedimentary granular fiber filter medium in the first stage of a filtration process, which includes a return prevention step in which a buoyancy adjustment mechanism and a return prevention member having an air reservoir are lowered, and before the filter medium layer compressed in the consolidation step returns to the open surface, the return prevention member is placed on the surface of the filter medium layer to maintain the consolidation of the filter medium layer, and a consolidation step in which the consolidated water stored in the filtration tank is drained from the bottom and the fiber filter medium is compressed to form a filter medium layer, and then the filtration process is started, so that the entire filter medium layer can form a stable state with a uniform and high degree of compaction , and clear treated water can be obtained stably for a long time from the beginning of operation. Also, the filtration process can be started in a state where the filter medium layer is prevented from loosening after consolidation.

本発明のろ過処理方法は、特に、空隙率が高く圧縮性の大きい繊維ろ材に有効で、ろ材層形成時に発生する緩みを防止できる。そのため、ろ過処理工程の前段で均一で高い圧密度のろ材層を形成するため、運転初期から安定したろ過処理を行い、ろ過終了時まで安定した水質の処理水を得ることができる。 The filtration method of the present invention is particularly effective for fibrous filter media with high porosity and high compressibility, and can prevent loosening that occurs when the filter layer is formed. Therefore, because a filter layer with a uniform and high degree of compression is formed at the early stage of the filtration process, stable filtration can be performed from the beginning of operation, and treated water with stable water quality can be obtained until the end of filtration.

本発明に係るろ過装置の縦断面図である。1 is a vertical cross-sectional view of a filtering device according to the present invention. 同じく、戻り防止部材の縦断面図である。FIG. 同じく、戻り防止部材の平面図である。FIG. 同じく、ろ過処理工程の模式図である。FIG. 同じく、洗浄工程の模式図である。FIG. 同じく、洗浄工程終了後の模式図である。FIG. 13 is a schematic diagram of the same after the cleaning process is completed. 同じく、戻り防止工程の模式図である。 FIG . 同じく、圧密工程の模式図である。 FIG .

図１は本発明に係るろ過装置の縦断面図である。
ろ過装置１は、円筒状のろ過槽２を立設し、内部に繊維ろ材３…を充填してろ過槽２下方の流出防止スクリーン４上にろ材層５を形成している。繊維ろ材３は沈降性の粒状繊維ろ材であって、球状や柱状等、形を限定しない。上部の供給管６から被処理水を供給し、ろ材層５にて懸濁物質を捕捉して処理水を下方の排出管７から外部に排出する。流出防止スクリーン４の下方には空洗管８を備えてあり、洗浄時に洗浄ブロワ９から洗浄管１０を介してろ過槽２に圧縮空気を噴射する。なお、ろ過槽２は多段に連設する構成としてもよい。また、必要に応じて供給管６側への繊維ろ材３の流出を防止するスクリーンをろ過槽２の上方に張設してもよい。 FIG. 1 is a vertical sectional view of a filtering device according to the present invention.
The filtration device 1 has a cylindrical filtration tank 2 that is erected, and a fibrous filter medium 3 is filled inside to form a filter medium layer 5 on an outflow prevention screen 4 below the filtration tank 2. The fibrous filter medium 3 is a sedimentary granular fibrous filter medium, and the shape is not limited to a sphere or a columnar shape. The water to be treated is supplied from a supply pipe 6 at the top, and the filter medium layer 5 captures suspended solids, and the treated water is discharged to the outside from a discharge pipe 7 at the bottom. An air washing pipe 8 is provided below the outflow prevention screen 4, and compressed air is sprayed from a washing blower 9 through a washing pipe 10 into the filtration tank 2 during washing. The filtration tank 2 may be configured to be connected in multiple stages. If necessary, a screen that prevents the outflow of the fibrous filter medium 3 toward the supply pipe 6 side may be stretched above the filtration tank 2.

図２，３は戻り防止部材の縦断面図および平面図である。
ろ過槽２の内部には、圧縮したろ材層５が上方の開放方向に緩み、ろ材層５の空隙率が不均一となることを防止する戻り防止部材１１を備える。 2 and 3 are a vertical sectional view and a plan view of the return prevention member.
The inside of the filter tank 2 is provided with a return prevention member 11 for preventing the compressed filter layer 5 from loosening in the upward opening direction and causing the porosity of the filter layer 5 to become non-uniform.

戻り防止部材１１は、円盤状の多孔板１２と、多孔板１２の上面に連結し他端の中央部から通水可能な二重筒で形成し空気溜り１８を有するケーシング１３と、調整錘１５と調整弁１６を備えた浮力調整機構１７とで構成している。浮力調整機構１７でケーシング１３の二重筒の間に形成した空気溜り１８に貯留した空気量を調整し、ろ過槽２内で戻り防止部材１１を上下に揺動自在とすることを特徴とする。 The return prevention member 11 is composed of a disk-shaped porous plate 12, a casing 13 formed of a double cylinder connected to the upper surface of the porous plate 12 and allowing water to pass through from the center of the other end, with an air reservoir 18, and a buoyancy adjustment mechanism 17 equipped with an adjustment weight 15 and an adjustment valve 16. The buoyancy adjustment mechanism 17 adjusts the amount of air stored in the air reservoir 18 formed between the double cylinders of the casing 13, allowing the return prevention member 11 to swing freely up and down within the filter tank 2.

多孔板１２は外周をろ過槽２内壁に近接させている。ろ過槽２とは繊維ろ材３が通過できない間隙に設定してあり、外周に摺動部材を周設してもよい。 The outer periphery of the perforated plate 12 is close to the inner wall of the filter tank 2. It is set in a gap between the filter tank 2 and the fiber filter material 3 that cannot pass through, and a sliding member may be installed around the outer periphery.

また、多孔板１２には全面に微小な通水孔を有している。通水孔は供給管６からの被処理水をろ材層５へ通水するとともに、上方への繊維ろ材３の流出を防止する。板材に微小孔を貫設、あるいは環状枠にメッシュ部材を張設してもよい。 The perforated plate 12 also has tiny water holes all over its surface. The water holes allow the water to be treated from the supply pipe 6 to pass through to the filter layer 5, and also prevent the fiber filter medium 3 from flowing upward. The tiny holes may be drilled through the plate, or a mesh member may be stretched over the annular frame.

なお、多孔板１２の鉛直方向には必要に応じて補強用のリブを設けてもよい。また、通水孔を有する多孔板１２を所定の間隔を設けて上下２段で設けると、下段の多孔板１２から流出した繊維ろ材３を上段の多孔板１２で防止できる。 If necessary, reinforcing ribs may be provided in the vertical direction of the perforated plate 12. Also, if perforated plates 12 with water passage holes are provided in two tiers, one above the other, with a specified distance between them, the upper perforated plate 12 can prevent the fiber filter material 3 from flowing out from the lower perforated plate 12.

多孔板１２の上方にはケーシング１３を連設している。ケーシング１３は多孔板１２と固定する外筒１９と、ケーシング１３の他端を閉塞し中央部に通水自在な孔部２０を有する蓋１４と、孔部２０から垂下した内筒２１で構成される。内筒２１は多孔板１２に向かって所定距離だけ延設されてあり、内筒２１と外筒１９の間は多孔板１２を通過した空気を一時的に貯留する空気溜り１８を形成している。蓋１４には調整弁１６を介装してあり、空気溜り１８に貯留されている空気量を調整する。空気量に応じて戻り防止部材１１の浮力を調整し、戻り防止部材１１を上下に揺動させる。 A casing 13 is connected above the perforated plate 12. The casing 13 is composed of an outer tube 19 fixed to the perforated plate 12, a lid 14 that closes the other end of the casing 13 and has a hole 20 in the center that allows water to pass through freely, and an inner tube 21 that hangs down from the hole 20. The inner tube 21 extends a specified distance toward the perforated plate 12, and an air reservoir 18 is formed between the inner tube 21 and the outer tube 19 to temporarily store air that has passed through the perforated plate 12. An adjustment valve 16 is installed in the lid 14 to adjust the amount of air stored in the air reservoir 18. The buoyancy of the return prevention member 11 is adjusted according to the amount of air, causing the return prevention member 11 to swing up and down.

外筒１９と内筒２１の直径や高さは、ろ過装置１の仕様やろ過槽２の直径、空気溜り１８の容量に応じて適宜決定する。なお、本実施例では通水可能な内筒２１を中心部に配置しているが、中心部から均等な位置に複数の内筒２１…を配置してもよい。 The diameters and heights of the outer tube 19 and the inner tube 21 are determined appropriately according to the specifications of the filtration device 1, the diameter of the filtration tank 2, and the capacity of the air reservoir 18. In this embodiment, the inner tube 21 through which water can pass is disposed at the center, but multiple inner tubes 21 may be disposed at equal positions from the center.

蓋１４は被処理液が外筒１９とろ過槽２の間に侵入し難いように、外周をろ過槽２内壁に近接させている。外周に摺動部材を周設してもよい。 The outer periphery of the lid 14 is close to the inner wall of the filtration tank 2 so that the liquid to be treated is unlikely to enter between the outer cylinder 19 and the filtration tank 2. A sliding member may be provided around the outer periphery.

浮力調整機構１７は、多孔板１２に載置した調整錘１５と、ケーシング１３の蓋１４に介装した調整弁１６とで構成している。 The buoyancy adjustment mechanism 17 is composed of an adjustment weight 15 placed on the perforated plate 12 and an adjustment valve 16 installed in the lid 14 of the casing 13.

調整錘１５は重力により戻り防止部材１１を下降させるもので、下降時に多孔板１２が傾斜しないよう中心部から均等に配置する。本実施例では円環状の調整錘１５を用いている。調整錘１５の重量は、ろ過装置１の仕様や空気溜り１８の容量に応じて適宜決定する。なお、本実施例では調整錘１５を多孔板１２に載置しているが、ケーシング１３の外筒１９や内筒２１、あるいは蓋１４に設けてもよい。 The adjustment weights 15 lower the return prevention member 11 by gravity, and are evenly positioned from the center so that the perforated plate 12 does not tilt when lowered. In this embodiment, a circular adjustment weight 15 is used. The weight of the adjustment weight 15 is determined appropriately according to the specifications of the filtration device 1 and the capacity of the air reservoir 18. Note that, although the adjustment weight 15 is placed on the perforated plate 12 in this embodiment, it may be provided on the outer tube 19 or inner tube 21 of the casing 13, or on the lid 14.

調整弁１６はケーシング１３の空気溜り１８に貯留する空気を外部に排出し、戻り防止部材１１の浮力を減少させるためのものである。空気を外部に排出する際に、戻り防止部材１１が傾斜しないよう複数の調整弁１６…を中心部から均等に配置することが望ましい。なお、空気溜り１８に連通する可撓管を蓋１４に接続し、他端をろ過槽２の頂部や側面に設けた調整弁１６に接続してもよい。 The adjustment valves 16 are intended to discharge air stored in the air reservoir 18 of the casing 13 to the outside, thereby reducing the buoyancy of the return prevention member 11. It is desirable to arrange multiple adjustment valves 16 evenly from the center so that the return prevention member 11 does not tilt when the air is discharged to the outside. A flexible tube communicating with the air reservoir 18 may be connected to the lid 14, and the other end may be connected to an adjustment valve 16 provided on the top or side of the filtration tank 2.

図４はろ過処理工程の模式図である。
ろ過処理工程Ｓ１は、ろ過槽２下方にろ材層５を圧密形成し、通水可能な戻り防止部材１１をろ材層５の表層に摺接させて、圧縮したろ材層５による開放面への戻りを防止した状態で行う。被処理水はろ過槽２上部の供給管６から供給される。ろ過槽２に供給された被処理水は、戻り防止部材１１の孔部２０から内筒２１を経て多孔板１２を通過してろ材層５に案内される。ろ材層５では被処理水中の懸濁物質を繊維ろ材３により捕捉し、処理水のみがろ材層５を通過してろ過槽２底部の排出管７から排出される。
この時、戻り防止部材１１の調整弁１６は閉止している。 FIG. 4 is a schematic diagram of the filtration process.
The filtration process S1 is performed by compacting the filter layer 5 below the filtration tank 2 and bringing a water-permeable backflow prevention member 11 into sliding contact with the surface of the filter layer 5 to prevent the compressed filter layer 5 from returning to the open surface. The water to be treated is supplied from a supply pipe 6 at the top of the filtration tank 2. The water to be treated supplied to the filtration tank 2 is guided from the holes 20 in the backflow prevention member 11 through the inner tube 21 and the porous plate 12 to the filter layer 5. In the filter layer 5, suspended solids in the water to be treated are captured by the fibrous filter medium 3, and only the treated water passes through the filter layer 5 and is discharged from the discharge pipe 7 at the bottom of the filtration tank 2.
At this time, the regulating valve 16 of the return prevention member 11 is closed.

図５は洗浄工程の模式図である。
長時間のろ過処理工程Ｓ１でろ材層５に目詰まりが発生した際には繊維ろ材３の洗浄を行う。洗浄工程Ｓ２ではろ過槽２の上方まで貯水した状態にてろ過槽２底部の空洗管８から洗浄用空気を噴射する。ろ過槽２に放出された気泡は圧縮されたろ材層５を緩和させつつ上昇する。戻り防止部材１１の多孔板１２を通過した気泡の一部は内筒２１からろ過槽２上方へと抜け、一部は空気溜り１８に貯留される。空気溜り１８の貯留量が増加し、浮力が調整錘１５を含めた戻り防止部材１１の重力より大きくなると戻り防止部材１１が上昇を開始する。ろ材層５の上方が開放され、繊維ろ材３が攪拌されるとともに繊維ろ材３で捕捉していた懸濁物質が剥離される。
この時、戻り防止部材１１の調整弁１６は閉止している。 FIG. 5 is a schematic diagram of the cleaning process.
When clogging occurs in the filter layer 5 during the long filtration process S1, the fiber filter medium 3 is washed. In the washing process S2, with water stored up to the top of the filter tank 2, washing air is sprayed from the air washing pipe 8 at the bottom of the filter tank 2. The air bubbles released into the filter tank 2 rise while relaxing the compressed filter layer 5. Some of the air bubbles that pass through the porous plate 12 of the return prevention member 11 escape from the inner tube 21 to the top of the filter tank 2, and some are stored in the air reservoir 18. When the amount of storage in the air reservoir 18 increases and the buoyancy becomes greater than the gravity of the return prevention member 11 including the adjustment weight 15, the return prevention member 11 starts to rise. The top of the filter layer 5 is opened, the fiber filter medium 3 is agitated, and the suspended matter captured by the fiber filter medium 3 is peeled off.
At this time, the regulating valve 16 of the return prevention member 11 is closed.

図６は洗浄工程終了後の模式図である。
洗浄工程Ｓ２の終了後、繊維ろ材３は自重により流出防止スクリーン４上に堆積する。ろ過槽２に洗浄水を貯留した状態であるため、戻り防止部材１１はろ過槽２の上方に上昇した位置で静置している。 FIG. 6 is a schematic diagram after the cleaning process is completed.
After the washing step S2 is completed, the fiber filter medium 3 is piled up on the overflow prevention screen 4 by its own weight. Since the washing water is stored in the filter tank 2, the return prevention member 11 is placed at a position elevated above the filter tank 2.

ろ材層５は自然沈降した状態であり、繊維ろ材３，３間で大きな空隙を有している。この状態で被処理液を通水すると、被処理液中の懸濁物質が繊維ろ材３で捕捉されずにろ材層５を通過して処理水とともに排出されてしまうため、ろ過処理工程Ｓ１の前段にろ材層５を圧密する各工程Ｓ３，Ｓ４を行う。 The filter layer 5 is in a naturally settled state, and there are large gaps between the fibrous filter media 3, 3. If the liquid to be treated is passed through in this state, suspended matter in the liquid to be treated will not be captured by the fibrous filter media 3, but will pass through the filter layer 5 and be discharged together with the treated water. Therefore, steps S3 and S4 are carried out prior to the filtration process S1 to consolidate the filter layer 5.

図７は戻り防止工程の模式図である。
戻り防止工程Ｓ３では戻り防止部材１１をろ材層５の表層へ向かって下降させる。具体的には、戻り防止部材１１の調整弁１６を開放し、空気溜り１８に貯留している空気をろ過槽２上方へ逃がす。空気溜り１８の空気貯留量が減少し、戻り防止部材１１の浮力が調整錘１５を含めた戻り防止部材１１の重力より小さくなると戻り防止部材１１が下降を開始する。戻り防止部材１１の下降速度は調整弁１６の開度や調整錘１５の重量等にて調整できる。ろ過槽２が密閉型である場合は、ろ過槽２上方に公知の空気抜き弁を設け、戻り防止工程Ｓ３で空気溜り１８の貯留空気を開放する間は空気抜き弁を開放する。 FIG. 7 is a schematic diagram of the anti-return process.
In the return prevention step S3, the return prevention member 11 is lowered toward the surface of the filter medium layer 5. Specifically, the adjustment valve 16 of the return prevention member 11 is opened to release the air stored in the air reservoir 18 above the filtration tank 2. When the amount of air stored in the air reservoir 18 decreases and the buoyancy of the return prevention member 11 becomes smaller than the gravity of the return prevention member 11 including the adjustment weight 15, the return prevention member 11 starts to descend. The descent speed of the return prevention member 11 can be adjusted by the opening of the adjustment valve 16, the weight of the adjustment weight 15, etc. When the filtration tank 2 is of a sealed type, a known air vent valve is provided above the filtration tank 2, and the air vent valve is opened while the stored air in the air reservoir 18 is released in the return prevention step S3.

戻り防止部材１１が所定の位置まで下降したことを検知して圧密工程Ｓ４を開始する。本実施例では、多孔板１２がろ材層５の表層に到達した後に圧密工程Ｓ４を開始するが、戻り防止部材１１が下降中に圧密工程Ｓ４を開始してもよい。 The consolidation process S4 is started when it is detected that the return prevention member 11 has descended to a predetermined position. In this embodiment, the consolidation process S4 is started after the perforated plate 12 has reached the surface of the filter layer 5, but the consolidation process S4 may also be started while the return prevention member 11 is descending.

なお、戻り防止部材１１の調整錘１５は、ろ材層５の上方への反発力を抑えるだけの重量とすることが望ましい。調整錘１５による戻り防止部材１１の重量が大きいと、ろ材層５の表層に静置した際に、特にろ材層５上層を戻り防止部材１１により圧縮してしまい、上層の圧縮率のみが高くなり、均一な空隙率のろ材層５の形成を阻害する。 It is preferable that the weight of the adjustment weight 15 of the return prevention member 11 is set to a weight sufficient to suppress the upward repulsive force of the filter medium layer 5. If the weight of the return prevention member 11 by the adjustment weight 15 is large, when the return prevention member 11 is placed on the surface layer of the filter medium layer 5, the upper layer of the filter medium layer 5 in particular will be compressed by the return prevention member 11 , and only the compression rate of the upper layer will be high, preventing the formation of a filter medium layer 5 with a uniform porosity.

図８は圧密工程の模式図である。
圧密工程Ｓ４では繊維ろ材３を圧密してろ材層５を形成する。具体的には、排出管７に介装する弁を開放し、洗浄工程時Ｓ２にろ過槽２上方まで貯水している洗浄水（圧密水）を一気に下方へ向かって排水する。戻り防止部材１１の上方の圧密水は、戻り防止部材１１の内筒２１に流入し、多孔板１２を通過して下方に向かって排水される。繊維ろ材３は圧密水をろ過槽２の底部方向へ流す際に生じる動圧によって、流出防止スクリーン４の上方で圧密され、充分な圧密度を有するろ材層５を形成する。圧密工程Ｓ４を行うと繊維ろ材同士の間隙が狭くなり、自然沈降時と比較してろ材層５の高さが低くなる。 FIG. 8 is a schematic diagram of the consolidation process.
In the consolidation step S4, the fibrous filter medium 3 is consolidated to form the filter medium layer 5. Specifically, the valve installed in the discharge pipe 7 is opened, and the cleaning water (consolidated water) stored up to the upper part of the filtration tank 2 during the cleaning step S2 is drained downwards in one go. The consolidated water above the return prevention member 11 flows into the inner tube 21 of the return prevention member 11, passes through the perforated plate 12, and is drained downwards. The fibrous filter medium 3 is consolidated above the outflow prevention screen 4 by the dynamic pressure generated when the consolidated water flows toward the bottom of the filtration tank 2, and forms the filter medium layer 5 having a sufficient degree of compaction. When the consolidation step S4 is performed, the gaps between the fibrous filter medium become narrower, and the height of the filter medium layer 5 becomes lower than that during natural settling.

この時、戻り防止部材１１もろ材層５の圧密による表層低下に同調して降下し、戻り防止部材１１の多孔板１２がろ材層５の表層に静置する。降下は戻り防止部材１１の重力および水流から受ける動圧による。ろ材層５の表層に静置する戻り防止部材１１の重力はろ材層５の圧縮による反発力より大きいため、ろ材層５が緩んで上方に展開することがなく、ろ材層５の圧密を維持する。同様に、ろ過処理工程Ｓ１時に被処理液を通水する際に下方のろ材層５を押圧することがない。 At this time, the return prevention member 11 also descends in sync with the lowering of the surface layer due to the compaction of the filter layer 5, and the perforated plate 12 of the return prevention member 11 rests on the surface layer of the filter layer 5. The descent is due to the gravity of the return prevention member 11 and the dynamic pressure it receives from the water flow. Since the gravity of the return prevention member 11 resting on the surface layer of the filter layer 5 is greater than the repulsive force caused by the compression of the filter layer 5, the filter layer 5 does not loosen and expand upward, and the compaction of the filter layer 5 is maintained. Similarly, the lower filter layer 5 is not pressed when the liquid to be treated is passed through during the filtration process S1.

本実施例では、圧密水として洗浄工程Ｓ２後にろ過槽２に貯留している洗浄水を利用しているが、洗浄水の排水後に外部から圧密水をろ過槽２に供給してもよい。洗浄水を圧密水として排出する際には、ろ過槽２底部に沈降した懸濁物質を同時に排出する。必要に応じてろ過槽２に圧密水を貯留して排水する圧密工程Ｓ４を複数回行ってもよい。 In this embodiment, the cleaning water stored in the filtration tank 2 after the cleaning step S2 is used as the consolidation water, but the consolidation water may be supplied to the filtration tank 2 from the outside after the cleaning water is drained. When the cleaning water is discharged as the consolidation water, the suspended matter that has settled to the bottom of the filtration tank 2 is discharged at the same time. If necessary, the consolidation step S4, in which the consolidation water is stored in the filtration tank 2 and then drained, may be performed multiple times.

ろ材層５の圧密後、戻り防止部材１１の調整弁１６は閉止し、図４に示すようにろ過処理工程Ｓ１を開始する。均一で高い圧密度のろ材層５を形成しているため運転初期から安定したろ過処理が可能となる。 After the filter layer 5 is compressed, the adjustment valve 16 of the return prevention member 11 is closed, and the filtration process S1 begins as shown in Figure 4. Since the filter layer 5 is formed with a uniform and high degree of compression, stable filtration can be performed from the beginning of operation.

本実施例では、戻り防止工程Ｓ３で戻り防止部材１１がろ材層５表層に到達した直後に圧密工程Ｓ４を開始しているが、ろ材層５が圧密された後に戻り防止部材１１をろ材層５の表層まで下降させるものであれば問題ない。ろ材層５が圧密工程Ｓ４で水流により圧縮され、その反発力により上方の開放面へ展開する前に、ろ材層５表層に戻り防止部材１１を静置させてろ材層５の展開を抑えることが重要である。
なお、必要に応じて戻り防止部材１１をろ過槽２の任意の位置に静止させる係止部材を備えてもよい。 In this embodiment, the consolidation step S4 is started immediately after the return prevention member 11 reaches the surface layer of the filter material layer 5 in the return prevention step S3, but there is no problem if the return prevention member 11 is lowered to the surface layer of the filter material layer 5 after the filter material layer 5 is consolidated. It is important to leave the return prevention member 11 stationary on the surface layer of the filter material layer 5 to suppress the expansion of the filter material layer 5 before the filter material layer 5 is compressed by the water flow in the consolidation step S4 and expands to the open surface above due to the repulsive force.
If necessary, a locking member may be provided to stop the return prevention member 11 at any position in the filter tank 2.

本発明によれば、ろ過処理工程の前段でろ材層を圧密し、運転初期から安定したろ過処理を行うことができる。表層ろ過になりやすい凝集ろ過や高濁度水、あるいはプール等の高清澄度が要求される特殊な用途にも捕捉率の高い繊維ろ材を使用でき、深層ろ過を行うことで洗浄頻度が少なく長時間のろ過処理工程を行うことができる有益なろ過処理方法となる。 According to the present invention, the filter media layer is compressed in the early stages of the filtration process, allowing for stable filtration from the beginning of operation. Fiber media with a high capture rate can be used for coagulation filtration, which is prone to surface filtration, highly turbid water, or special applications that require high clarity, such as pools, and by performing deep filtration, it is possible to carry out the filtration process over a long period of time with less frequent cleaning, making this a beneficial filtration method.

２ ろ過槽
３ 繊維ろ材
５ ろ材層
１７ 浮力調整機構
１８ 空気溜り
１１ 戻り防止部材
Ｓ１ ろ過処理工程
Ｓ３ 戻り防止工程
Ｓ４ 圧密工程 2 Filtration tank 3 Fiber filter medium 5 Filter medium layer 17 Buoyancy adjustment mechanism 18 Air reservoir 11 Return prevention member S1 Filtration process S3 Return prevention process S4 Consolidation process

Claims (1)

ろ過処理工程（Ｓ１）の前段で沈降性の粒状繊維ろ材（３）を圧密するろ過処理方法において、
浮力調整機構（１７）と空気溜り（１８）を有する戻り防止部材（１１）を下降させ、圧密工程（Ｓ４）で圧縮されたろ材層（５）による開放面への戻りが発生する前に、ろ材層（５）表層に戻り防止部材（１１）を静置させてろ材層（５）の圧密を維持する戻り防止工程（Ｓ３）と、
ろ過槽（２）に貯留した圧密水を底部から排水し、繊維ろ材（３）を圧縮してろ材層（５）を形成する圧密工程（Ｓ４）と、
を実施した後、
ろ過処理工程（Ｓ１）を開始する
ことを特徴とするろ過処理方法。 In a filtration method for consolidating a sedimentary granular fiber filter medium (3) in a stage prior to a filtration step (S1),
a return prevention step (S3) in which a return prevention member (11) having a buoyancy adjustment mechanism (17) and an air reservoir (18) is lowered, and the return prevention member (11) is left stationary on the surface of the filter medium layer (5) to maintain the consolidation of the filter medium layer (5) before the filter medium layer (5) compressed in the consolidation step (S4) returns to the open surface ;
A consolidation step (S4) of discharging the consolidation water stored in the filtration tank (2) from the bottom and compressing the fiber filter medium (3) to form a filter medium layer (5);
After carrying out the above,
A filtration method, comprising starting a filtration process (S1).
JP2021136793A 2021-08-25 2021-08-25 Filtration method Active JP7498888B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2021136793A JP7498888B2 (en) 2021-08-25 2021-08-25 Filtration method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2021136793A JP7498888B2 (en) 2021-08-25 2021-08-25 Filtration method

Publications (2)

Publication Number Publication Date
JP2023031356A JP2023031356A (en) 2023-03-09
JP7498888B2 true JP7498888B2 (en) 2024-06-13

Family

ID=85415730

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2021136793A Active JP7498888B2 (en) 2021-08-25 2021-08-25 Filtration method

Country Status (1)

Country Link
JP (1) JP7498888B2 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7498887B2 (en) 2021-08-25 2024-06-13 株式会社石垣 Filtration method

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002191908A (en) 2000-12-27 2002-07-10 Daiei Sangyo Kk Filter and septic tank
JP2005034099A (en) 2003-07-18 2005-02-10 Kato Tekko Kk Underwater driver and apparatus using the same driver
CN201760139U (en) 2010-04-22 2011-03-16 上海凡清环境工程有限公司 Mechanical-regulation longitudinal flow fiber bundle filter device
JP2011212645A (en) 2010-04-02 2011-10-27 Swing Corp Filtration method and filtration apparatus of emulsified water
KR101150675B1 (en) 2011-09-20 2012-05-25 신지훈 The constant filtration system which has a backwash-water and the filtration method
WO2020261883A1 (en) 2019-06-26 2020-12-30 パナソニックＩｐマネジメント株式会社 Filtration device for water treatment
JP2023031355A (en) 2021-08-25 2023-03-09 株式会社石垣 Filtration processing method

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002191908A (en) 2000-12-27 2002-07-10 Daiei Sangyo Kk Filter and septic tank
JP2005034099A (en) 2003-07-18 2005-02-10 Kato Tekko Kk Underwater driver and apparatus using the same driver
JP2011212645A (en) 2010-04-02 2011-10-27 Swing Corp Filtration method and filtration apparatus of emulsified water
CN201760139U (en) 2010-04-22 2011-03-16 上海凡清环境工程有限公司 Mechanical-regulation longitudinal flow fiber bundle filter device
KR101150675B1 (en) 2011-09-20 2012-05-25 신지훈 The constant filtration system which has a backwash-water and the filtration method
WO2020261883A1 (en) 2019-06-26 2020-12-30 パナソニックＩｐマネジメント株式会社 Filtration device for water treatment
JP2023031355A (en) 2021-08-25 2023-03-09 株式会社石垣 Filtration processing method

Also Published As

Publication number Publication date
JP2023031356A (en) 2023-03-09

Similar Documents

Publication Publication Date Title
JP7498888B2 (en) Filtration method
US9498740B2 (en) Washbox
CA2037799A1 (en) Backwash method and apparatus
US4139473A (en) Filter
US5441651A (en) Method and apparatus for processing sludge
CN102186551A (en) Filter with adjustable porosity
JP2010279860A5 (en)
US2562730A (en) Filter tube
JPH0318483B2 (en)
CN201120186Y (en) Fibre bundle filter
JPS5811008A (en) Filter device
JP5353927B2 (en) Filtration device and operation method thereof
JP7498887B2 (en) Filtration method
JPH03181303A (en) Liquid filter
US4738786A (en) Pressure filter enclosure
CN206081824U (en) Single automatic vertical filter press
JP3809648B2 (en) Moving filter filter
US3513091A (en) Countercurrent solid-liquid contacting system
JP7493143B2 (en) Filtration device and filtration method
JP2002191908A (en) Filter and septic tank
JP3815616B2 (en) Upflow filter
US10702805B2 (en) Washbox
JP2024046951A (en) Filtration apparatus and filtration treatment method
US4986008A (en) Method for dewatering water-containing particle collections with the aid of gas under pressure
CN216764396U (en) Anti-backflow ion exchanger

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20230731

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20240313

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20240313

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20240315

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20240501

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20240514

R150 Certificate of patent or registration of utility model

Ref document number: 7498888

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150