JPH06226012A - Filtering and concentrating method and device - Google Patents
Filtering and concentrating method and deviceInfo
- Publication number
- JPH06226012A JPH06226012A JP1999193A JP1999193A JPH06226012A JP H06226012 A JPH06226012 A JP H06226012A JP 1999193 A JP1999193 A JP 1999193A JP 1999193 A JP1999193 A JP 1999193A JP H06226012 A JPH06226012 A JP H06226012A
- Authority
- JP
- Japan
- Prior art keywords
- stock solution
- filtrate
- chamber
- filter
- filtration
- 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.)
- Granted
Links
- 238000001914 filtration Methods 0.000 title claims abstract description 53
- 238000000034 method Methods 0.000 title claims abstract description 22
- 239000007788 liquid Substances 0.000 claims abstract description 31
- 239000002699 waste material Substances 0.000 claims abstract description 25
- 239000011550 stock solution Substances 0.000 claims description 69
- 239000000706 filtrate Substances 0.000 claims description 41
- 239000000243 solution Substances 0.000 claims description 12
- 239000000463 material Substances 0.000 claims description 7
- 238000011084 recovery Methods 0.000 claims description 5
- 238000011001 backwashing Methods 0.000 description 16
- 230000007423 decrease Effects 0.000 description 4
- 239000012065 filter cake Substances 0.000 description 4
- 239000000725 suspension Substances 0.000 description 4
- 238000005192 partition Methods 0.000 description 3
- 238000009825 accumulation Methods 0.000 description 2
- 239000012141 concentrate Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は懸濁液を濾過して濾液と
濃縮懸濁液とを分離回収する装置及びその方法に関し、
特に濾材上に堆積する瀘滓の除去効率を高めることによ
り濾過操業能率を改良した濾過濃縮装置及び濾過濃縮方
法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and method for filtering a suspension to separate and collect a filtrate and a concentrated suspension,
In particular, the present invention relates to a filtration / concentration device and a filtration / concentration method in which filtration efficiency is improved by increasing the removal efficiency of the residue accumulated on the filter medium.
【0002】[0002]
【従来の技術】大量の懸濁液を濾過濃縮するための装置
として、下部の原液室内に筒状濾材を垂設し上部に該筒
状濾材の内部と連通する濾液室を設けた縦型の濾過機が
知られている。このような濾過機を用いて原液を濾過濃
縮するには、ポンプ等により原液室に原液を加圧供給し
て濾液室から濾液を回収する。そして濾材の周りに濾滓
が蓄積して濾過能率が低下したときにはまず原液の供給
を停止し、次に原液室の下部に接続した排液管を開いて
原液を排出すると同時に必要に応じて濾液室に加圧空気
などを供給して濾液室内の濾液を逆流させることにより
濾材を逆洗し、濾材から剥離した濾滓を含んだ液を排液
管を通じて別途に設けた廃液槽などへ送るようにし、濾
過能率を回復させるようにしている。2. Description of the Related Art As a device for filtering and concentrating a large amount of a suspension, a vertical type filter is provided in which a cylindrical filter medium is vertically provided in a lower stock solution chamber, and a filtrate chamber communicating with the inside of the cylindrical filter medium is provided in an upper part. Filters are known. In order to filter and concentrate the stock solution using such a filter, the stock solution is pressurized and supplied to the stock solution chamber by a pump or the like to recover the filtrate from the filtrate chamber. When filter residue accumulates around the filter medium and the filtration efficiency decreases, first stop the supply of the stock solution, then open the drainage pipe connected to the bottom of the stock solution chamber to discharge the stock solution and, at the same time, remove the filtrate if necessary. The filter medium is backwashed by supplying pressurized air to the chamber and backflowing the filtrate in the filtrate chamber, and the liquid containing the filter cake separated from the filter medium is sent to a separately provided waste liquid tank through a drain pipe. In order to recover the filtration efficiency.
【0003】しかしながらこのような濾過濃縮方法で
は、濾材上に濾滓が蓄積したときに濾過操作を停止して
濾材の洗浄再生操作を行うので、懸濁物濃度の高い原液
を処理する場合には頻繁に濾過工程を中断しなければな
らず、逆洗工程に要する時間ばかりでなく工程の切り換
えのために要する時間も長くなるために、濾過機の稼働
効率が低下してしまうという問題があった。However, in such a filtration and concentration method, when the filter residue is accumulated on the filter material, the filtration operation is stopped and the filter material is washed and regenerated. Therefore, when treating a stock solution having a high suspension concentration, Since the filtration process must be frequently interrupted, and not only the time required for the backwash process but also the time required for switching the processes are long, there is a problem that the operating efficiency of the filter is reduced. .
【0004】これに対して濾材逆洗工程に要する時間を
短縮するために、濾液室内に供給する空気の圧力を高く
して濾液の逆流速度を早める手段が従来から採用されて
いるが、濾液室内の圧力を高くすると耐圧性の高い装置
が必要で経済的な制約があるほか時間短縮にも限度があ
り、更に濾材が傷み易いという問題もあった。On the other hand, in order to shorten the time required for the backwashing step of the filter medium, a means for increasing the pressure of air supplied into the filtrate chamber to accelerate the backflow rate of the filtrate has been conventionally adopted. When the pressure is increased, a device with high pressure resistance is required, which is economically limited, and there is a limit to time reduction, and there is a problem that the filter medium is easily damaged.
【0005】[0005]
【発明が解決しようとする課題】そこで本発明は、濾過
機の稼働効率を更に高めることを可能とする濾過濃縮装
置及び濾過濃縮方法を提供しようとするものであり、濾
過機の運転に当たって濾過工程と逆洗工程との切り換え
時間を短縮し、かつ逆洗工程を単純化することによって
上記の目的を達成しようとするものである。SUMMARY OF THE INVENTION Therefore, the present invention is intended to provide a filtration concentrating device and a filtration concentrating method capable of further increasing the operation efficiency of the filtration device. The object of the present invention is to achieve the above object by shortening the switching time between the backwashing step and the backwashing step and simplifying the backwashing step.
【0006】[0006]
【課題を解決するための手段】従って本発明の濾過濃縮
装置は、原液貯槽と、濾材を隔てて原液室と濾液室とを
設けた濾過機と、濾液貯槽と、廃液槽と、原液ポンプを
介して該原液貯槽と該原液室とを結ぶ原液供給路と、該
濾液室と該濾液貯槽とを結ぶ濾液回収路と、該原液室の
底部と該廃液槽とを結ぶ排液路と、該廃液槽内容物を減
圧排除できる吸引ポンプとを備えたものである。Therefore, the filtration and concentrating apparatus of the present invention comprises a stock solution storage tank, a filter provided with a stock solution chamber and a filtrate chamber with a filter material therebetween, a filtrate storage tank, a waste solution tank, and a stock solution pump. A stock solution supply path connecting the stock solution storage tank and the stock solution chamber via a filtrate recovery path connecting the stock solution chamber and the filtrate storage tank; and a drainage path connecting the bottom of the stock solution chamber and the waste solution tank, It is provided with a suction pump capable of removing the contents of the waste liquid tank under reduced pressure.
【0007】そして本発明の濾過濃縮方法は、上記の濾
過濃縮装置を用いて原液貯槽から原液供給路を介して原
液を濾過機に圧送し濾液を濾液貯槽に回収する濾過操作
実施中に、排液路を急激に開いて原液室底部から予め吸
引ポンプにより減圧された廃液槽内に瀘滓濃縮液を急速
に排出すると共に濾液室から逆流する濾液で濾材から瀘
滓を剥離させ、次いで排液路を閉じて濾過操作に戻るこ
とを特徴とする。The filtration and concentration method of the present invention uses the above-described filtration and concentration device to discharge the stock solution from the stock solution storage tank through the stock solution supply passage to the filter under pressure to collect the filtrate into the filtrate storage tank. The liquid channel is suddenly opened and the concentrated residue of the residue is rapidly discharged from the bottom of the stock solution chamber into the waste tank which has been decompressed by a suction pump in advance, and the filtrate flowing back from the filtrate chamber is used to remove the residue from the filter medium. It is characterized by closing the passage and returning to the filtration operation.
【0008】[0008]
【作用】本発明によれば、原液ポンプを運転して濾過工
程を実施している状態で排液路の弁を開くのみで逆洗工
程に入ることができ、また弁を閉じるのみで逆洗工程か
ら濾過工程に戻ることができる。従って濾滓の蓄積が少
なくて濾材の逆洗が容易なときに短時間の逆洗を行って
濾過能率を回復させる操作を繰り返して実施することに
より、長時間の連続運転を行って濾過機の稼働効率を大
幅に改善することが可能である。According to the present invention, the backwashing process can be started only by opening the valve of the drainage path while the stock solution pump is operating and the filtering process is being performed, and the backwashing process can be performed only by closing the valve. The process can return to the filtration process. Therefore, when the backwashing of the filter medium is easy because the accumulation of filter residue is small and the backwashing is carried out for a short period of time, the operation of recovering the filtration efficiency is repeated to carry out continuous operation for a long time, It is possible to greatly improve operating efficiency.
【0009】[0009]
【実施例】以下、本発明の濾過濃縮装置を図1によって
説明する。図において、1は原液貯槽であり、2は濾過
機、3は濾液貯槽、4は廃液槽である。濾過機2は中央
部の仕切り板2aを挟んで下部に原液室2bが、上部に
濾液室2cが形成されている。また仕切り板2aには筒
状の濾材2dが垂設されており、濾材2dの内部は濾液
室2cと連通している。DESCRIPTION OF THE PREFERRED EMBODIMENTS The filtration and concentrating device of the present invention will be described below with reference to FIG. In the figure, 1 is a stock solution storage tank, 2 is a filter, 3 is a filtrate storage tank, and 4 is a waste solution tank. The filter 2 has a stock solution chamber 2b in the lower part and a filtrate chamber 2c in the upper part with a partition plate 2a in the center part sandwiched therebetween. Further, a cylindrical filter medium 2d is vertically provided on the partition plate 2a, and the inside of the filter medium 2d communicates with the filtrate chamber 2c.
【0010】原液ポンプ5は原液貯槽1と原液室2bと
を連絡している原液供給路Aの途中に設けられており、
原液ポンプ5の二次側から原液供給路Aと別れて原液を
原液貯槽1に戻すための原液返送路Bが設けられてい
る。一方、濾液室2cからは濾液回収路Cによって濾液
を濾液貯槽3に送るようになっており、また原液室2b
の底部からは排出弁6を介して排液路Dを通じて廃液を
廃液槽4に落とすことができるようになっている。この
廃液槽4内の廃液及びガスは吸引ポンプ7により吸引さ
れて図示しない廃液処理装置に送り出されるようになっ
ており、従って廃液槽4は吸引ポンプ7の運転により減
圧した状態に保たれる。The stock solution pump 5 is provided in the middle of a stock solution supply path A which connects the stock solution storage tank 1 and the stock solution chamber 2b.
A stock solution return path B for returning the stock solution to the stock solution storage tank 1 is provided separately from the stock solution supply path A from the secondary side of the stock solution pump 5. On the other hand, the filtrate from the filtrate chamber 2c is sent to the filtrate storage tank 3 through the filtrate recovery path C, and the stock solution chamber 2b is also used.
The waste liquid can be dropped into the waste liquid tank 4 from the bottom through the drain valve D via the drain valve 6. The waste liquid and the gas in the waste liquid tank 4 are sucked by the suction pump 7 and sent to a waste liquid processing device (not shown). Therefore, the waste liquid tank 4 is kept depressurized by the operation of the suction pump 7.
【0011】このように構成された濾過濃縮装置を利用
して原液の濾過工程を実施するに当たっては、原液ポン
プ5を運転して原液供給路Aを通じて原液貯槽1内の原
液を原液室2bに送り込み、濾材2dによって濾過され
た濾液を蓄圧状態となった濾液室2cから濾液回収路C
を経て濾液貯槽3に回収する。このとき原液返送路Bは
濾過速度を調整するために原液の一部が原液貯槽1に戻
るように僅かに開いていてもよい。When carrying out the step of filtering the stock solution using the filtration and concentrating device thus constructed, the stock solution pump 5 is operated to feed the stock solution in the stock solution storage tank 1 through the stock solution supply passage A into the stock solution chamber 2b. , A filtrate recovery passage C from the filtrate chamber 2c in which the filtrate filtered by the filter material 2d is in a pressure-accumulated state.
And then collected in the filtrate storage tank 3. At this time, the undiluted solution return passage B may be slightly opened so that part of the undiluted solution returns to the undiluted solution storage tank 1 in order to adjust the filtration rate.
【0012】こうして濾過工程を継続すると濾材2d上
には濾滓が堆積し、次第に濾過速度が低下するから、原
液返送路Cを絞って原液の戻り量を減らし、原液室2b
の内圧を高めると同時に濾過速度が低下しないように維
持することができる。しかし本発明においては、濾滓の
堆積量があまり多くならないうちに次の逆洗工程に移る
のが良い。When the filtration process is continued in this way, filter residue is deposited on the filter medium 2d and the filtration rate gradually decreases. Therefore, the stock solution return passage C is narrowed to reduce the amount of the stock solution returned, and the stock solution chamber 2b.
It is possible to increase the internal pressure of the resin while maintaining the filtration rate so as not to decrease. However, in the present invention, it is better to move to the next backwashing step before the amount of the accumulated filter cake becomes too large.
【0013】本発明における逆洗工程は、上記のような
濾過工程の継続中、すなわち排出弁6が閉じられたまま
原液ポンプ5を運転している状態で、あらかじめ吸引ポ
ンプ7を運転して廃液槽4内が減圧された状態のときに
実施する。すなわち、濾過工程の継続中に排出弁6を急
激に開放すると原液室2b内の原液は排液路Dを通じて
廃液槽4内に吸引され、原液室2b内は一時的に減圧さ
れる。そうすると蓄圧状態と濾液室2c内の濾液が濾材
2dを通って原液室2bに逆流し、濾材2d上の濾滓は
剥離して原液室2b内の原液中に落下する。In the backwashing step in the present invention, the suction pump 7 is operated in advance while the stock solution pump 5 is being operated while the filtration step as described above is being continued, that is, with the discharge valve 6 being closed. This is performed when the pressure inside the tank 4 is reduced. That is, when the discharge valve 6 is suddenly opened during the continuation of the filtration process, the stock solution in the stock solution chamber 2b is sucked into the waste solution tank 4 through the drainage path D, and the stock solution chamber 2b is temporarily depressurized. Then, the pressure accumulation state and the filtrate in the filtrate chamber 2c flow back to the stock solution chamber 2b through the filter medium 2d, and the filter residue on the filter material 2d is peeled off and dropped into the stock solution in the stock solution chamber 2b.
【0014】そこで所定の時間、例えば10秒程度の時
間経過後に排出弁6を閉止すると逆洗工程は終了して濾
過工程に戻る。そのとき濾材2dから剥離して原液中に
浮遊している濾滓は大部分が塊状であり、再び濾材2d
上には殆ど付着せずに沈降して原液室2bの底部に堆積
するから、次の濾過工程の実施には何等の障害にもなら
ない。こうして沈降した濾滓は次の逆洗工程の際に原液
と混合した廃液として廃液槽4内に吸引排出されること
になる。When the discharge valve 6 is closed after a lapse of a predetermined time, for example, about 10 seconds, the backwashing process ends and the process returns to the filtering process. At that time, most of the filter cake separated from the filter medium 2d and floating in the undiluted solution is a lump, and again the filter medium 2d
Since it hardly deposits on the top and settles and deposits on the bottom of the stock solution chamber 2b, it does not hinder the execution of the next filtration step. The filter cake thus settled is sucked and discharged into the waste liquid tank 4 as a waste liquid mixed with the stock solution in the next backwashing step.
【0015】このような濾過工程と逆洗工程とは、原液
ポンプ5を運転している状態で単に排出弁6を開閉する
のみで連続して切り換えることができるものであり、工
程切り換えに要する時間は殆どなくまた逆洗時間も非常
に短いので、濾過運転には殆ど支障を与えない。The filtration step and the backwash step can be continuously switched by simply opening and closing the discharge valve 6 while the stock solution pump 5 is operating. Since the backwashing time is very short and the backwashing time is very short, the filtration operation is hardly disturbed.
【0016】[0016]
【発明の効果】本発明の濾過濃縮方法によれば、原液ポ
ンプを運転したままで濾過と逆洗とを連続して切り換え
にながら実施できるから、濾過工程と逆洗工程との切り
換えに際しての待ち時間が不要であって濾過機の運転時
間に対する実質の濾過時間の割合、すなわち濾過機の稼
働効率を著しく高めることができるばかりでなく、短時
間の逆洗を頻繁に行っても稼働効率があまり低下しない
ので濾過機の連続稼働時間を大幅に延長することがで
き、従って装置の規模に比較して大きな濾過能力が発揮
される。更に本発明の濾過濃縮装置は本発明の濾過濃縮
方法を実施するに適した装置であり、原液ポンプの起動
頻度を大幅に少なくできるから起動時の電力が少なくな
り、ポンプ運転用電源の容量も大きく取らずに済み経済
的であるうえ寿命も長くなるという利点がある。また逆
洗に際して加圧空気を導入する必要がないから、耐圧設
計の不要な経済的な装置を組むことができ、その上過度
の濾過圧力を加える必要がないから濾材の損傷が少ない
という効果もある。According to the filtration and concentration method of the present invention, it is possible to carry out while continuously switching the filtration and the backwash while the stock solution pump is operating. Therefore, there is no need to wait when switching between the filtration step and the backwash step. The time is not required and the ratio of the actual filtering time to the operating time of the filter, that is, the operating efficiency of the filter can be significantly increased, and the operating efficiency is not so high even if frequent backwashing is performed for a short time. Since it does not decrease, the continuous operation time of the filter can be greatly extended, and thus a large filtering capacity is exhibited in comparison with the scale of the apparatus. Furthermore, the filtration concentrating device of the present invention is a device suitable for carrying out the filtration concentrating method of the present invention. Since the starting frequency of the stock solution pump can be greatly reduced, the power consumption at the time of starting is reduced, and the capacity of the pump operating power source There is an advantage that it does not need to be taken large and is economical and has a long life. In addition, because it is not necessary to introduce pressurized air during backwashing, an economical device that does not require pressure resistance design can be assembled, and since it is not necessary to apply excessive filtration pressure, the damage to the filter medium is small. is there.
【図1】本発明の濾過濃縮装置の構成図である。FIG. 1 is a configuration diagram of a filtration and concentration device of the present invention.
1 原液貯槽 2 濾過機 2a 仕切り板 2b 原液室 2c 濾液室 2d 濾材 3 濾液貯槽 4 廃液槽 5 原液ポンプ 6 排出弁 7 吸引ポンプ A 原液供給路 B 原液返送路 C 濾液回収路 D 排液路 1 stock solution storage tank 2 filter 2a partition plate 2b stock solution chamber 2c filtrate room 2d filter medium 3 filtrate storage tank 4 waste solution tank 5 stock solution pump 6 discharge valve 7 suction pump A stock solution supply path B stock solution return path C filtrate recovery path D waste solution path
───────────────────────────────────────────────────── フロントページの続き (72)発明者 柳下 和彦 愛知県名古屋市中村区則武町1丁目22−4 トーカンマンション906号 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhiko Yanashita 1-22-4 Noritakecho, Nakamura-ku, Nagoya, Aichi Tokan Mansion 906
Claims (2)
室とを設けた濾過機と、濾液貯槽と、廃液槽と、原液ポ
ンプを介して該原液貯槽と該原液室とを結ぶ原液供給路
と、該濾液室と該濾液貯槽とを結ぶ濾液回収路と、該原
液室の底部と該廃液槽とを結ぶ排液路と、該廃液槽内容
物を減圧排除できる吸引ポンプとを備えたことを特徴と
する濾過濃縮装置。1. A stock solution storage tank, a filter provided with a stock solution chamber and a filtrate chamber with a filter medium in between, a filtrate storage tank, a waste solution tank, and a stock solution connecting the stock solution storage tank and the stock solution chamber via a stock solution pump. A supply path, a filtrate recovery path that connects the filtrate chamber and the filtrate storage tank, a drainage path that connects the bottom of the stock solution chamber and the waste liquid tank, and a suction pump that can remove the contents of the waste liquid tank under reduced pressure. A filtering and concentrating device.
原液貯槽から原液供給路を介して原液を濾過機に圧送し
濾液を濾液貯槽に回収する濾過操作実施中に、排液路を
急激に開いて原液室底部から予め吸引ポンプにより減圧
された廃液槽内に瀘滓濃縮液を急速に排出すると共に濾
液室から逆流する濾液で濾材から瀘滓を剥離させ、次い
で排液路を閉じて濾過操作に戻ることを特徴とする濾過
濃縮方法。2. Using the filtration concentrating device according to claim 1,
A waste liquid tank in which the drainage path is suddenly opened and the suction pump is used to reduce the pressure from the bottom of the stock solution chamber during the filtration operation in which the stock solution is pumped from the stock solution storage tank to the filtration machine and the filtrate is collected in the filtrate storage tank. A method for filtering and concentrating, characterized in that a concentrated filter solution is rapidly discharged into the filter material, and the filtered material flows backward from the filtrate chamber to remove the filter residue from the filter medium, and then the drainage channel is closed to return to the filtering operation.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
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JP01999193A JP3255474B2 (en) | 1993-02-08 | 1993-02-08 | Filtration concentration device and filtration concentration method |
US08/191,695 US5498349A (en) | 1993-02-08 | 1994-02-04 | Filtration concentration apparatus and method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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JP01999193A JP3255474B2 (en) | 1993-02-08 | 1993-02-08 | Filtration concentration device and filtration concentration method |
Publications (2)
Publication Number | Publication Date |
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JPH06226012A true JPH06226012A (en) | 1994-08-16 |
JP3255474B2 JP3255474B2 (en) | 2002-02-12 |
Family
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JP01999193A Expired - Fee Related JP3255474B2 (en) | 1993-02-08 | 1993-02-08 | Filtration concentration device and filtration concentration method |
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JP (1) | JP3255474B2 (en) |
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1993
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JP3255474B2 (en) | 2002-02-12 |
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