JPH0258000B2 - - Google Patents
Info
- Publication number
- JPH0258000B2 JPH0258000B2 JP11619182A JP11619182A JPH0258000B2 JP H0258000 B2 JPH0258000 B2 JP H0258000B2 JP 11619182 A JP11619182 A JP 11619182A JP 11619182 A JP11619182 A JP 11619182A JP H0258000 B2 JPH0258000 B2 JP H0258000B2
- Authority
- JP
- Japan
- Prior art keywords
- nozzle
- aeration
- pipe
- compressed air
- aeration nozzle
- 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.)
- Expired - Lifetime
Links
- 238000005273 aeration Methods 0.000 claims description 43
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 24
- 239000002002 slurry Substances 0.000 claims description 12
- 238000002347 injection Methods 0.000 claims description 11
- 239000007924 injection Substances 0.000 claims description 11
- 238000000034 method Methods 0.000 claims description 10
- 239000000243 solution Substances 0.000 claims description 6
- 229910052602 gypsum Inorganic materials 0.000 claims description 5
- 239000010440 gypsum Substances 0.000 claims description 5
- 239000007788 liquid Substances 0.000 description 12
- 230000000694 effects Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- 239000011575 calcium Substances 0.000 description 2
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000920 calcium hydroxide Substances 0.000 description 1
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 1
- 235000011116 calcium hydroxide Nutrition 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000011343 solid material Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000005514 two-phase flow Effects 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
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
- Aeration Devices For Treatment Of Activated Polluted Sludge (AREA)
- Preventing Corrosion Or Incrustation Of Metals (AREA)
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、石膏等のスラリーを含む溶液中に設
けられる曝気ノズルの閉塞防止方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for preventing clogging of an aeration nozzle provided in a solution containing a slurry of gypsum or the like.
（従来の技術）
スラリー溶液（処理液）中に、曝気ノズルで圧
縮空気を噴出することにより、スラリー溶液の酸
化、撹拌等を行なう場合、従来の一般ノズルで
は、スラリー溶液の性状によつては、ノズル先端
の内壁にスケールが付着、成長し、該スケールが
やがてはノズルを閉塞し、ついには運転不能にな
ることがあつた。特に石膏（CaSO4・2H2O）、
炭酸カルシウム（CaCO3）、消石灰（Ca（OH）2）
等のスラリーを含む溶液中で、この閉塞現象の発
生は顕著である。(Prior art) When performing oxidation, stirring, etc. of a slurry solution (processing liquid) by jetting compressed air with an aeration nozzle, a conventional general nozzle may not be able to In some cases, scale adheres to and grows on the inner wall of the nozzle tip, and the scale eventually blocks the nozzle, eventually rendering it inoperable. Especially gypsum (CaSO 4 2H 2 O),
Calcium carbonate (CaCO 3 ), slaked lime (Ca(OH) 2 )
The occurrence of this clogging phenomenon is remarkable in a solution containing a slurry such as.
この曝気ノズルの閉塞原因は、曝気ノズルによ
り空気がスラリー液中に噴出する際、気流の流
れ、動圧の変化、液面変動による静圧変化等の影
響により、空気圧の低い部分にスラリー液が飛び
込み、該スラリー液がノズル内部璧に付着する
が、この付着したスラリー液は、空気により瞬間
に乾燥されて固形物となる。この固形物の上にさ
らにスラリー液が付着して乾燥と湿潤の状態を繰
返えし、スケールが成長して行き、ついにはノズ
ルを閉塞せしめるためである。 The cause of this blockage of the aeration nozzle is that when air is ejected into the slurry liquid by the aeration nozzle, the slurry liquid flows into areas with low air pressure due to the effects of air flow, changes in dynamic pressure, changes in static pressure due to changes in the liquid level, etc. The slurry liquid flies in and adheres to the inner wall of the nozzle, but this adhered slurry liquid is instantly dried by air and becomes a solid substance. This is because the slurry liquid is further deposited on top of this solid material, repeating dry and wet conditions, and scale grows, eventually clogging the nozzle.
第１図に従来の曝気装置の一例を示すが、同図
において、１は円筒型の貯槽本体であり、同貯槽
本体１の中心上方より圧縮空気供給配管２が垂設
されており、該配管２は槽本体１の中央付近に位
置するヘツダー管４に接続されている。５は該ヘ
ツダー管４より斜下方に放射状に分岐された複数
本の分岐管で、それら分岐管５の各先端には、曝
気ノズル６が接続されており、圧縮空気の噴出口
となつている。７は槽本体１内に同心的に配設さ
れた内筒でサポート板８により槽本体１に支持さ
れている。 An example of a conventional aeration device is shown in Fig. 1. In the figure, 1 is a cylindrical storage tank main body, and a compressed air supply pipe 2 is vertically installed from above the center of the storage tank main body 1. 2 is connected to a header pipe 4 located near the center of the tank body 1. Reference numeral 5 denotes a plurality of branch pipes that branch radially downward from the header pipe 4, and an aeration nozzle 6 is connected to each tip of the branch pipe 5, which serves as a compressed air outlet. . Reference numeral 7 denotes an inner cylinder disposed concentrically within the tank body 1, and is supported by the tank body 1 by a support plate 8.
上記のように構成された曝気装置の各曝気ノズ
ル６より噴出される圧縮空気の空気粒のエアリフ
ト効果により、内筒７の内側の処理液（スラリー
液）は、気液２相流となつて上昇し、上部の処理
液９が内筒７の外側を下降し、スラリー溶液は循
環、撹拌されて処理されるようになつている。こ
のような曝気装置では、さきに述べたように、ノ
ズル６の先端にスケール１０が、第２図に示すよ
うに付着形成され、該スケール１０が成長して行
き、ついには、第３図に示すようにノズル６を閉
塞するに至る。 Due to the air lift effect of air particles of compressed air ejected from each aeration nozzle 6 of the aeration device configured as above, the processing liquid (slurry liquid) inside the inner cylinder 7 becomes a gas-liquid two-phase flow. The processing liquid 9 in the upper part moves down outside the inner cylinder 7, and the slurry solution is circulated, stirred, and processed. In such an aeration device, as mentioned earlier, the scale 10 is deposited on the tip of the nozzle 6 as shown in FIG. 2, and the scale 10 grows until finally, as shown in FIG. As shown, the nozzle 6 is blocked.
このような曝気ノズルの閉塞を防止する方法と
して、例えば特公昭57−27749号公報に記載され
た曝気用散気管の詰り防止方法がある。この詰り
防止方法は、曝気槽内に空気を排気する散気管内
に少なくとも一つのガラス又は金属製の小遊動体
を配して該遊動体を散気管内に遊動させ、かつ、
該散気管内に水を常時注入して散気管の排出孔の
目詰りを防止するように構成されている。 As a method for preventing such clogging of an aeration nozzle, there is a method for preventing clogging of an aeration diffuser pipe described in, for example, Japanese Patent Publication No. 57-27749. This clogging prevention method includes disposing at least one small floating body made of glass or metal in an aeration pipe that exhausts air into an aeration tank, and causing the floating body to move inside the aeration pipe, and
It is configured to constantly inject water into the air diffuser pipe to prevent clogging of the discharge hole of the air diffuser pipe.
（発明が解決しようとする課題）
前述のような曝起用散気管の詰り防止方法は、
散気管内に小遊動体を配して、その衝撃力と流体
圧とでスケールを剥離するようになつているた
め、多量の空気と水を必要とする等の問題点があ
る。(Problem to be solved by the invention) The method for preventing clogging of the aeration diffuser pipe as described above is as follows:
Since small floating bodies are placed in the air diffuser pipe and the impact force and fluid pressure are used to remove scale, there are problems such as the need for large amounts of air and water.
本発明は、曝気ノズルの先端内壁を常に湿潤状
態に保持することにより、スケールの付着、成長
を防止する方法を提供することを目的とするもの
である。 An object of the present invention is to provide a method for preventing scale adhesion and growth by constantly keeping the inner wall of the tip of an aeration nozzle in a moist state.
（課題を解決するための手段）
曝気装置の貯槽内に、注水配管を接続した圧縮
空気供給配管を垂直に設置し、同配管の下端に複
数の分岐管を下方に傾斜させて取付ける。(Means for solving the problem) A compressed air supply pipe connected to a water injection pipe is vertically installed in the storage tank of the aeration device, and a plurality of branch pipes are installed at the lower end of the pipe so as to be inclined downward.
分岐管の外端（下端）に、鉛直下方を指向した
単一の直進孔部を有する曝気ノズルを設ける。 An aeration nozzle having a single straight hole oriented vertically downward is provided at the outer end (lower end) of the branch pipe.
（作用）
注水配管より供給された水は必ず曝気ノズルの
ノズル先端にいたり、同ノズル先端の内壁面を常
に湿潤状態に保つ。従つて、同内壁面付近の石膏
等のCaスケール成分は該湿潤水により希釈され
ることとなり、スケールが析出しない。また仮に
スケールが析出したとしても、同ノズル先端の内
壁面は常に湿つた状態であるので、スケールは内
壁面に付着することなく、連続的もしくは断続的
に供給される水により流出する。よつて、ノズル
の閉塞が防げる。(Function) The water supplied from the water injection pipe is always at the tip of the aeration nozzle, and the inner wall surface of the tip of the nozzle is always kept moist. Therefore, Ca scale components such as gypsum near the inner wall surface will be diluted by the moist water, and no scale will precipitate. Furthermore, even if scale were to precipitate, the inner wall surface at the tip of the nozzle is always in a moist state, so the scale will not adhere to the inner wall surface and will flow out due to the water that is continuously or intermittently supplied. Therefore, clogging of the nozzle can be prevented.
（実施例）
第４図及び第５図を参照しながら、本発明につ
き具体的に説明する。(Example) The present invention will be specifically described with reference to FIGS. 4 and 5.
第４図及び第５図は、本発明を実施する装置の
一例を示すが、それらの図で、１は貯槽本体、２
は圧縮空気供給配管、４はヘツダー管、５は分岐
管、６は曝気ノズル、７は内筒、８はサポート
板、をそれぞれ示し、それら部材の構成、作用及
び相互の関係構造は、圧縮空気供給配管２にＴ型
継手管２ａを介して注水配管３を接続し、該注水
配管３から圧縮空気供給管２内へ注水できるよう
にした点以外は、上記従来の曝気装置の各部材と
ほぼ同様である。（均等部分には同一符号を付し
てある。）
本発明を実施する曝気装置の一例は、上記の如
く圧縮空気供給配管２に注水配管３を連続し、該
注水配管３を介して少量の水１２を圧縮空気供給
配管２に連続的または断続的に注入するように構
成したものである。 FIGS. 4 and 5 show an example of an apparatus for carrying out the present invention, in which 1 indicates a storage tank body, 2
4 indicates a compressed air supply pipe, 4 indicates a header pipe, 5 indicates a branch pipe, 6 indicates an aeration nozzle, 7 indicates an inner cylinder, and 8 indicates a support plate. The components of the conventional aeration system are almost the same as those of the above-mentioned conventional aeration system, except that a water injection pipe 3 is connected to the supply pipe 2 via a T-shaped joint pipe 2a, and water can be injected from the water injection pipe 3 into the compressed air supply pipe 2. The same is true. (Equivalent parts are given the same reference numerals.) In an example of an aeration system implementing the present invention, a water injection pipe 3 is connected to the compressed air supply pipe 2 as described above, and a small amount of water is supplied through the water injection pipe 3. The water 12 is configured to be continuously or intermittently injected into the compressed air supply pipe 2.
いま、本装置の運転を開始すると、圧縮空気供
給配管２からの圧縮空気は各曝気ノズル６から噴
出されて、従来装置同様の曝気効果を発揮する
が、この際、注水配管３からの水１２は圧縮空気
供給配管２内の圧縮空気中でミスト状態となり、
これにより圧縮空気供給配管２及び各曝気ノズル
６の内壁面は、絶えず濡れた状態となる。そのた
め、各曝気ノズル６の内壁面へのスケールの付着
力が低下するため、該スケールは圧縮空気流で押
し出されて付着しなくなる。この結果、各曝気ノ
ズル６の閉塞現象は発生しない。 Now, when the device starts operating, the compressed air from the compressed air supply pipe 2 is ejected from each aeration nozzle 6, producing the same aeration effect as the conventional device. becomes a mist in the compressed air in the compressed air supply pipe 2,
As a result, the inner wall surfaces of the compressed air supply pipe 2 and each aeration nozzle 6 are constantly kept wet. Therefore, the adhesion of scale to the inner wall surface of each aeration nozzle 6 is reduced, and the scale is pushed out by the compressed air flow and no longer adheres. As a result, the phenomenon of clogging of each aeration nozzle 6 does not occur.
なお、注水配管より供給する水は、ノズル先端
を常に湿らす程度の水量でよく、例えばノズル先
端を水により洗浄する方式のものに比べ、はるか
に少ない供給水量でよい。 Note that the amount of water supplied from the water injection pipe may be sufficient to constantly moisten the nozzle tip, and the amount of water supplied may be much smaller than, for example, a system in which the nozzle tip is washed with water.
（発明の効果）
本発明は、石膏等のスラリーを含む溶液中に設
けられる曝気ノズルの閉塞防止方法において、注
水配管を接続した圧縮空気供給配管の下端にヘツ
ダー管を設け、同ヘツダー管より複数の分岐管を
放射状に且つ下向きに配置し、各分岐管の下端に
単一の直進孔部を有する曝気ノズルをそのノズル
先端が鉛直下方に向くように取付け、上記注水配
管より供給した水が、上記圧縮空気供給配管、ヘ
ツダー管及び曝気ノズルをへて上記ノズル先端の
内壁面にいたり、この内壁面を常に湿潤状態に保
持することにより、次の効果を有する。(Effects of the Invention) The present invention provides a method for preventing blockage of an aeration nozzle installed in a solution containing slurry such as gypsum, in which a header pipe is provided at the lower end of a compressed air supply pipe connected to a water injection pipe, and a plurality of header pipes are connected to the header pipe. The branch pipes are arranged radially and downward, and an aeration nozzle having a single straight hole is attached to the lower end of each branch pipe so that the tip of the nozzle faces vertically downward, and the water supplied from the water injection pipe is By passing through the compressed air supply pipe, header pipe, and aeration nozzle to the inner wall surface at the tip of the nozzle, and keeping this inner wall surface constantly moist, the following effects are achieved.
(1) 曝気ノズルの形状、材質如何に拘らず、曝気
ノズルへのスケールの付着、成長が防止され、
空気流量、圧力も最低限での運転が可能にな
る。(1) Regardless of the shape or material of the aeration nozzle, scale adhesion and growth on the aeration nozzle is prevented.
Operation with minimum air flow rate and pressure is possible.
(2) 従つて、曝気ノズルの保守、点検が不要にな
る。(2) Therefore, maintenance and inspection of the aeration nozzle becomes unnecessary.
第１図は従来の曝気装置の一例の略示的側断面
図、第２図は曝気ノズル内壁へのスケールの付着
状態説明図、第３図は成長スケールによる曝気ノ
ズルの閉塞状態説明図、第４図及び第５図は、本
発明方法を実施する曝気装置の一例の概略説明図
で、第４図は側断面図、第５図は平面図である。
１：貯槽本体、２：圧縮空気供給配管、３：注
水配管、４：ヘツダー管、５：分岐管、６：曝気
ノズル、７：内筒、８：サポート板、９：廃水等
の液体、１０：スケール、１１：圧縮空気、１
２：水。
Fig. 1 is a schematic side sectional view of an example of a conventional aeration device, Fig. 2 is an explanatory diagram of the state of adhesion of scale to the inner wall of the aeration nozzle, Fig. 3 is an explanatory diagram of the state of blockage of the aeration nozzle by growing scale, 4 and 5 are schematic explanatory diagrams of an example of an aeration apparatus for carrying out the method of the present invention, with FIG. 4 being a side sectional view and FIG. 5 being a plan view. 1: Storage tank body, 2: Compressed air supply piping, 3: Water injection piping, 4: Header pipe, 5: Branch pipe, 6: Aeration nozzle, 7: Inner cylinder, 8: Support plate, 9: Liquid such as waste water, 10 : Scale, 11: Compressed air, 1
2: Water.
Claims (1)
曝気ノズルの閉塞防止方法において、注水配管を
接続した圧縮空気供給配管の下端にヘツダー管を
設け、同ヘツダー管より複数の分岐管を放射状に
且つ下向きに配置し、各分岐管の下端に単一の直
進孔部を有する曝気ノズルをそのノズル先端が鉛
直下方に向くように取付け、上記注水配管より供
給した水が、上記圧縮空気供給配管、ヘツダー管
及び曝気ノズルをへて上記ノズル先端の内壁面に
いたり、この内壁面を常に湿潤状態に保持するこ
とを特徴とする曝気ノズルの閉塞防止方法。1. In a method for preventing blockage of an aeration nozzle installed in a solution containing slurry such as gypsum, a header pipe is provided at the lower end of a compressed air supply pipe connected to a water injection pipe, and multiple branch pipes are connected radially and downward from the header pipe. An aeration nozzle having a single straight hole is installed at the lower end of each branch pipe so that the tip of the nozzle faces vertically downward. and a method for preventing clogging of an aeration nozzle, which comprises passing through the aeration nozzle to the inner wall surface of the tip of the nozzle and keeping the inner wall surface constantly moist.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57116191A JPS596990A (en) | 1982-07-06 | 1982-07-06 | Method of inhibiting clogging of aerating nozzle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57116191A JPS596990A (en) | 1982-07-06 | 1982-07-06 | Method of inhibiting clogging of aerating nozzle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS596990A JPS596990A (en) | 1984-01-14 |
| JPH0258000B2 true JPH0258000B2 (en) | 1990-12-06 |
Family
ID=14681082
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57116191A Granted JPS596990A (en) | 1982-07-06 | 1982-07-06 | Method of inhibiting clogging of aerating nozzle |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS596990A (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4939023A (en) * | 1984-08-13 | 1990-07-03 | Canon Kabushiki Kaisha | Opto-magnetic recording medium |
| DE10066287B4 (en) * | 1999-10-18 | 2007-03-29 | Juki Corp., Chofu | Electronic sewing machine, for zigzag stitching, comprises arrangement for input of needle swing data in blocks and combining them into stitch program |
| JP4743162B2 (en) * | 2007-01-29 | 2011-08-10 | Ｊｆｅエンジニアリング株式会社 | Diffuser and diffuser |
| JP5535861B2 (en) * | 2010-10-08 | 2014-07-02 | 三菱重工業株式会社 | Aeration apparatus and seawater flue gas desulfurization apparatus equipped with the aeration apparatus |
| JP2012187522A (en) * | 2011-03-10 | 2012-10-04 | Jfe Engineering Corp | Air diffuser |
| JP5700537B2 (en) * | 2011-03-28 | 2015-04-15 | 三機工業株式会社 | Air diffuser system and air diffuser cleaning method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5727749A (en) * | 1980-06-20 | 1982-02-15 | Montedison Spa | Manufacture of multilayer structure from sheet containing synthetic fiber |
-
1982
- 1982-07-06 JP JP57116191A patent/JPS596990A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5727749A (en) * | 1980-06-20 | 1982-02-15 | Montedison Spa | Manufacture of multilayer structure from sheet containing synthetic fiber |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS596990A (en) | 1984-01-14 |
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