WO2017077774A1 - Bassin de décantation et son procédé de fonctionnement - Google Patents

Bassin de décantation et son procédé de fonctionnement Download PDF

Info

Publication number
WO2017077774A1
WO2017077774A1 PCT/JP2016/077634 JP2016077634W WO2017077774A1 WO 2017077774 A1 WO2017077774 A1 WO 2017077774A1 JP 2016077634 W JP2016077634 W JP 2016077634W WO 2017077774 A1 WO2017077774 A1 WO 2017077774A1
Authority
WO
WIPO (PCT)
Prior art keywords
raw water
tank
tank body
water introduction
stirring
Prior art date
Application number
PCT/JP2016/077634
Other languages
English (en)
Japanese (ja)
Inventor
哲 清水
Original Assignee
栗田工業株式会社
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 栗田工業株式会社 filed Critical 栗田工業株式会社
Publication of WO2017077774A1 publication Critical patent/WO2017077774A1/fr

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
    • B01D21/02—Settling tanks with single outlets for the separated liquid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
    • B01D21/24—Feed or discharge mechanisms for settling tanks

Definitions

  • the present invention relates to a sedimentation tank for separating fine suspended substances and the like from water to be treated and an operation method thereof.
  • sedimentation separation using a solid-liquid separation tank is widely adopted as means for separating the sludge mixed liquid into treated water and sludge.
  • a sludge zone sludge blanket layer
  • turbidity and fine SS in the sludge mixed solution are filtered and separated by flowing the gas from the distributor into the lower part of the sludge zone and passing through the sludge zone (for example, Patent Documents 1 and 2).
  • a tubular distributor extends in the radial direction from the lower end of the feed well, and a large number of openings are provided at intervals on the side of the distributor, and the raw water (sludge mixture) is supplied to the opening. Spill through.
  • Patent Document 2 a rectangular frame-shaped distributor having a straight tubular side is installed at the bottom of the settling tank, and a liquid outflow opening extending in the longitudinal direction of each side is provided on the bottom surface of the distributor.
  • the opening for raw water outflow may be clogged with sludge and foreign substances, and the maintenance is troublesome.
  • the present invention has been made in view of the above-described conventional situation, and an object thereof is to provide a sedimentation tank having a simple structure and good maintainability and an operation method thereof.
  • the precipitation tank of the present invention is a precipitation tank comprising a tank body and a raw water introduction part for introducing raw water into the lower part of the tank body, the tank body having a cylindrical peripheral wall part,
  • the elevation angle of the tapered portion with respect to the horizontal plane is 50 ° to 70 °.
  • the tapered portion is continuous with the bottom surface of the tank body, the raw water introduction portion has a discharge port for discharging raw water toward the bottom surface, and the diameter of the bottom surface is It is larger than the diameter of the discharge port.
  • the apparatus further includes a stirring body provided between the bottom surface of the tank body and the raw water introduction section, and the stirring body is connected to a rotating shaft arranged in the vertical direction in the tank body, The rotating shaft may be disposed through the raw water introduction portion.
  • the raw water introduction section has an insertion hole through which the rotating shaft is inserted, and a passage hole through which the stirring body passes when the stirring body is disposed to be lowered from above the tank body toward the bottom surface.
  • an elastic cover may be provided in the insertion hole and the passage hole.
  • the operation method of the settling tank of the present invention is a method for operating the settling tank of the first invention, wherein a sludge blanket is formed in the tank body, and the raw water is introduced from the raw water introduction section into the tank body.
  • the flow rate is 0.35 m / s or less.
  • the raw water discharged from the raw water introduction portion hits the bottom surface of the tank body, and along the tapered portion. An upward flow is formed, and a uniform upward flow as a whole can be passed through the sludge blanket.
  • the raw water introduction part can be a simple configuration that discharges raw water to the bottom surface of the tank body, and a sedimentation tank with good maintainability can be obtained.
  • the sedimentation tank 1 is provided in the tank body 2, the raw water introduction part 10 installed in the lower part (near the bottom) in the tank body 2, and the middle part in the vertical direction of the peripheral wall part 2a of the tank body 2 or slightly higher than that.
  • the trough 6 etc. which take out the treated water (supernatant water) which was turbidized when passing through.
  • the inside of the receiving tank 4 is the receiving chamber 4a.
  • the concentrated sludge is taken out from the lower part of the receiving tank 4.
  • the peripheral wall 2a of the tank body 2 is cylindrical, and the axial direction is the vertical direction.
  • the lower end of the taper part 2c continues to the periphery of the bottom surface 2b of the tank body 2, and the upper end of the taper part 2c continues to the lower end of the peripheral wall part 2a.
  • the tapered portion 2c has a smaller diameter toward the lower side. Accordingly, the inner diameter D 1 of the cylindrical part of the tank body 2 is larger than the diameter D 2 of the bottom surface 2b.
  • the elevation angle ⁇ of the tapered portion 2c with respect to the horizontal plane is 50 ° to 70 °, and preferably 55 ° to 70 °.
  • the elevation angle ⁇ is preferably 55 ° to 65 °, particularly about 60 °.
  • the agitating device 5 is arranged vertically on a drive unit 5a such as a motor, the shaft center part of the tank body 2, and is rotationally driven by the drive unit 5a, and is attached to the lowermost end of the rotation shaft 5b.
  • a drive unit 5a such as a motor
  • the stirring bodies 5d and 5e are paddle blades composed of a plurality of blades extending in the radial direction from the rotating shaft 5b.
  • the stirring bodies 5d and 5e extend in the four radiation directions.
  • the stirring member 5c is a single paddle blade that extends from the lowermost end of the rotating shaft 5b in a direction perpendicular to the axial direction.
  • the stirring body 5c is disposed below the discharge port 10c of the raw water introduction unit 10, for example, directly above the bottom surface 2b.
  • the stirring bodies 5d and 5e are arranged above the raw water introduction unit 10.
  • the uppermost stirring body 5e is positioned below the lower edge of the outlet 3.
  • Stirrer 5d, 5e turning diameter is preferably about 50 to 95% of the inner diameter (diameter) D 1 of the cylindrical part of the tank body 2.
  • the turning diameter of the stirring body 5c is preferably about 80 to 95% of the diameter D2 of the bottom surface 2b of the tank body 2 .
  • the raw water introduction part 10 has a straight pipe part 10a that penetrates the taper part 2c of the tank body 2 and extends in the horizontal direction, and a bent part 10b that is located on the distal end side of the straight pipe part 10a and bent downward (see FIG. 2 and 3).
  • the opening at the lower end of the bent portion 10b is a discharge port 10c that discharges raw water toward the bottom surface 2b. Discharged from the discharge port 10c raw water dispersed, and in order to sludge deposition area is not too large, the diameter D 2 of the bottom surface 2b, 1.15 ⁇ 3 times the diameter D 3 of the discharge port 10c It is preferable that
  • the raw water flow rate (raw water introduction flow rate) introduced into the tank body 2 from the raw water introduction unit 10 is preferably 0.35 m / s or less, and more preferably 0.22 m / s or less.
  • the raw water introduction flow rate is preferably 0.01 m / s or more.
  • the raw water discharged from the discharge port 10c hits the bottom surface 2b and is dispersed. If the height H 1 to the discharge port 10c of the raw water inlet portion 10 from the bottom surface 2b of the tank body 2 is too small, lateral discharge flow rate is increased, it becomes difficult to uniformly disperse the raw water. On the other hand, if the height H 1 is too large, the dead space below the tank body 2 increases. Therefore, the height H 1 is preferably about the same as the diameter D 3 of the discharge port 10 c, for example, about 0.8 to 1.2 times the diameter D 3 .
  • the height H 2 of to the top of the tapered portion 2c (lower part of the peripheral wall 2a) is the height required for uniform dispersion of the raw water, the raw water inlet portion 10 installation height
  • the elevation angle ⁇ of the tapered portion 2c with respect to the horizontal plane, the inner diameter D 1 of the tank body 2, and the diameter D 2 of the bottom surface 2b are determined.
  • the height H 3 to the lower edge of the outlet 3 taking into account the clarification of raw water, it is preferably 400mm or more.
  • the height H 4 from the lower edge of the outlet 3 to the water surface of the treated water is set to the inner diameter D 1 of the cylindrical portion of the tank body 2. It is preferably 0.5 times or more.
  • the height H 5 of the tank body 2 is preferably 2500 mm or less.
  • the rotating shaft 5b of the agitator 5 and the bent portion 10b of the raw water introduction portion 10 are both disposed at the axial center of the tank body 2, and the rotating shaft 5b is inserted into the bent portion 10b as shown in FIG.
  • An insertion hole 10d is provided.
  • a passage hole 10e through which the stirring member 5c passes is formed in a slit shape extending in the vertical direction.
  • the upper part of the passage hole 10e is connected to the insertion hole 10d.
  • the insertion hole 10d is provided with a cover 11 that closes the space between the peripheral edge of the insertion hole 10d and the rotation shaft 5b when the rotation shaft 5b is inserted.
  • the cover 11 is an elastic cover made of a material having elasticity such as rubber.
  • the cover 11 is provided along the periphery of the insertion hole 10d, and an opening 11a through which the rotation shaft 5b is inserted is provided at the center.
  • the cover 11 is provided with a slit 11b so as to be connected to a slit 12c described later.
  • Covers 12a and 12b are provided so as to close the passage hole 10e.
  • a slit 12c is provided between the cover 12a and the cover 12b.
  • the covers 12a and 12b are elastic covers made of a material having elasticity such as rubber.
  • the rotating shaft 5b When installing the stirring device 5, as shown in FIG. 4a, the rotating shaft 5b is lowered from above the tank body 2 toward the bottom surface 2b. At this time, the positions of the rotating shaft 5b and the insertion hole 10d are aligned, and the extending direction of the stirring member 5c is aligned with the passage hole 10d. Even if the position of the rotating shaft 5b is slightly deviated from the position of the opening 11a of the cover 11, the cover 11 has elasticity, so the rotating shaft 5b in contact with the cover 11 is guided to the opening 11a.
  • a material having good slidability with the stirring member 5c is preferable to use as the material of the covers 11, 12a, 12b.
  • a member having good slidability with the stirrer 5 c may be provided in a portion in contact with the stirrer 5 c.
  • the raw water is discharged downward at a slow flow rate from the discharge port 10c of the raw water introduction section 10, hits the bottom surface 2b of the tank body 2, forms an upward flow along the tapered portion 2c, and becomes a uniform upward flow as a whole. Pass the sludge blanket S.
  • the agitation bodies 5c to 5e agitate the sludge blanket S, the aggregated floc is adsorbed on the pellets of the sludge blanket S and is compacted by the collision of the pellets.
  • Raw water flows out of the trough 6 as treated water that has been turbidized when passing through the sludge blanket S. Since the suspended substance is adsorbed by the flocs in the sludge blanket S, the blanket interface rises. When the interface reaches the height of the outlet 3, the floc in the sludge blanket S flows out from the outlet 3 to the receiving chamber 4a. The sludge accumulated and concentrated in the receiving chamber 4a is taken out from the bottom of the receiving chamber 4a.
  • Stirring by the stirring body 5c is preferably such that the stirring strength in the space from the bottom surface 2b of the tank body 2 to the discharge port 10b of the raw water introduction section 10 is 0.01 to 0.5 s ⁇ 1 in terms of G value.
  • An average speed gradient value (G value) represented by the following formula is used as an indicator of the stirring intensity of the stirring and mixing by the stirring blades, and is determined by the size, the number of the stirring blades, and the number of rotations.
  • Stirring by the stirring bodies 5e and 5d is preferably such that the stirring strength in the space from the raw water introduction part 10 to the lower edge of the outlet 3 is 2 to 50 s ⁇ 1 in terms of G value.
  • the agitation with this agitation strength promotes the growth of flocs of the sludge blanket S.
  • the raw water introduction unit 10 has a simple structure for discharging raw water downward, and a distributor having a complicated structure having a large number of openings is unnecessary. Therefore, apparatus cost can be suppressed and maintainability can be improved.
  • the raw water introduction part 10 is provided in the tank lower part, and the straight pipe part 10a penetrates the taper part 2c of the tank body 2, but like the precipitation tank 1A shown in FIG.
  • the raw water introduction part 10 may be provided in the upper part of the tank, and the straight pipe part 10 a may penetrate the peripheral wall part 2 a of the tank body 2.
  • the peripheral wall 2a of the tank body 2 is not limited to a cylindrical shape, and may be a rectangular tube with a polygonal cross section.
  • Example 1 In treating raw water using the sedimentation tank 1 shown in FIG. 1, whether or not a circulating flow can be formed by the tapered portion 2c and whether or not a sludge blanket S can be formed were examined by CFD analysis.
  • analysis program “ANSY CFX” manufactured by ANSYS was used.
  • the simulation conditions are as follows.
  • Raw water SS concentration 100mg / L
  • Raw water flow rate 10m 3 / hr
  • Raw water discharge flow rate 0.16m / s SS sedimentation speed: 55.2 ⁇ exp ( ⁇ 0.07 ⁇ X) [m / hr]
  • X is the raw water SS concentration
  • the inner diameter D 1 of the cylindrical portion of the tank body 2 1000 mm
  • Diameter D 3 of the discharge port 10c of the raw water introduction part 10 150 mm Height H 1 from the bottom surface 2b of the tank body 2 to the discharge port 10c of the raw water introduction part 10: 150 mm Height H 3 from the upper part of the taper part 2c to the lower edge of the outlet 3 : 700 mm
  • the simulation was performed with the elevation angle ⁇ of the tapered portion 2c with respect to the horizontal plane in increments of 5 ° from 45 ° to 80 °.
  • the results are as follows.
  • a blanket can be formed by setting the elevation angle ⁇ to 50 ° to 70 °, and blanket formation can be improved by setting the elevation angle ⁇ to 55 ° to 70 °.
  • Example 2 The diameter D 3 and the raw water discharge flow rate of the discharge port 10c is varied, and whether the sludge blanket S can be formed was examined by CFD analysis.
  • the elevation angle ⁇ of the tapered portion 2c with respect to the horizontal plane was 60 °.
  • Other simulation conditions were the same as those in Example 1. The results are as follows.
  • a blanket can be formed by setting the discharge flow rate to 0.35 m / s or less, and blanket formation is improved by setting the discharge flow rate to 0.22 m / s or less.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Mixers Of The Rotary Stirring Type (AREA)
  • Separation Of Suspended Particles By Flocculating Agents (AREA)

Abstract

L'invention concerne un bassin de décantation ayant une structure simple et une excellente maintenabilité, et son procédé de fonctionnement. Un bassin de décantation (1) selon ce mode de réalisation comprend un corps de bassin (2) et une unité d'introduction d'eau brute (10) pour introduire l'eau brute dans la partie inférieure à l'intérieur du corps de bassin (2). Le corps de bassin (2) comporte une partie de paroi périphérique de forme cylindrique (2a) et une partie effilée (2c) reliée sur le côté de fond de la partie de paroi périphérique (2a), le diamètre de cette dernière diminuant vers le côté inférieur. L'angle d'élévation de la partie effilée (2c) par rapport à un plan horizontal est de 50-70°.
PCT/JP2016/077634 2015-11-02 2016-09-20 Bassin de décantation et son procédé de fonctionnement WO2017077774A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2015215806A JP6269635B2 (ja) 2015-11-02 2015-11-02 沈殿槽及びその運転方法
JP2015-215806 2015-11-02

Publications (1)

Publication Number Publication Date
WO2017077774A1 true WO2017077774A1 (fr) 2017-05-11

Family

ID=58661860

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2016/077634 WO2017077774A1 (fr) 2015-11-02 2016-09-20 Bassin de décantation et son procédé de fonctionnement

Country Status (3)

Country Link
JP (1) JP6269635B2 (fr)
TW (1) TW201722532A (fr)
WO (1) WO2017077774A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4834044Y1 (fr) * 1970-12-14 1973-10-15
JPS513650Y2 (fr) * 1972-12-18 1976-02-02
JPH01107813A (ja) * 1987-09-14 1989-04-25 A Ahlstroem Oy 濾床型浄化装置
JP2007209905A (ja) * 2006-02-09 2007-08-23 Kajima Corp 嫌気性バイオリアクター
US20110272346A1 (en) * 2008-12-24 2011-11-10 Degremont Quick static decanter for prethickening water treatment sludge, and plant including such a decanter

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4834044Y1 (fr) * 1970-12-14 1973-10-15
JPS513650Y2 (fr) * 1972-12-18 1976-02-02
JPH01107813A (ja) * 1987-09-14 1989-04-25 A Ahlstroem Oy 濾床型浄化装置
JP2007209905A (ja) * 2006-02-09 2007-08-23 Kajima Corp 嫌気性バイオリアクター
US20110272346A1 (en) * 2008-12-24 2011-11-10 Degremont Quick static decanter for prethickening water treatment sludge, and plant including such a decanter

Also Published As

Publication number Publication date
JP6269635B2 (ja) 2018-01-31
TW201722532A (zh) 2017-07-01
JP2017087091A (ja) 2017-05-25

Similar Documents

Publication Publication Date Title
CN103347580B (zh) 多室水力旋流器
RU2316483C2 (ru) Установка и способ осаждения минеральных взвесей
US4054514A (en) Sedimentation apparatus with flocculating feed well
JP4765022B2 (ja) 固液分離装置
CN105936531B (zh) 一种诱导结晶沉淀水处理设备
JP2005520672A (ja) 濃縮装置用２区分式原料供給井
JP5799940B2 (ja) 沈殿槽及びその運転方法
CN110642353A (zh) 一种絮凝搅拌器
JP2010207670A (ja) 濁水の処理装置
JPH01270913A (ja) 活性スラッジを含んだ排水の懸濁液から活性スラッジを分離するために使用される沈澱タンク
SE1051368A1 (sv) Vattenrenare och metod för att rena vatten
FI87893C (fi) Saett att anrika malmsuspension med hjaelp av kraftig foerberedande blandning och samtidig flotation samt anordningar foer genomfoerande av detta
JP6269635B2 (ja) 沈殿槽及びその運転方法
US3385576A (en) Apparatus for dispersing a gas in a liquid
JPH08187405A (ja) 凝集沈殿装置
JP2010058066A (ja) 加圧浮上装置
JP2017013029A (ja) 凝集槽及び凝集処理方法
WO2012156169A1 (fr) Dispositif permettant la séparation de gaz contenus dans une suspension
KR101935369B1 (ko) 수처리조 및 이를 이용한 수처리장치
JPH0138523B2 (fr)
EP3626336A1 (fr) Système de mélange pour l'introduction de substances chimiques dans un fluide à traiter
JPH10337406A (ja) 凝集処理装置
NO20160241A1 (en) Method and apparatus for purification of water from aquaculture plants
CN110902787A (zh) 流化床沉淀装置及其污水处理系统
CN114314748B (zh) 污水处理反应器

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16861843

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 16861843

Country of ref document: EP

Kind code of ref document: A1