CA1325982C - Filter bed clarifier - Google Patents
Filter bed clarifierInfo
- Publication number
- CA1325982C CA1325982C CA000577204A CA577204A CA1325982C CA 1325982 C CA1325982 C CA 1325982C CA 000577204 A CA000577204 A CA 000577204A CA 577204 A CA577204 A CA 577204A CA 1325982 C CA1325982 C CA 1325982C
- Authority
- CA
- Canada
- Prior art keywords
- tank
- opening
- disposed
- feed pipe
- cone
- 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 - Fee Related
Links
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C11/00—Regeneration of pulp liquors or effluent waste waters
- D21C11/0064—Aspects concerning the production and the treatment of green and white liquors, e.g. causticizing green liquor
- D21C11/0078—Treatment of green or white liquors with other means or other compounds than gases, e.g. in order to separate solid compounds such as sodium chloride and carbonate from these liquors; Further treatment of these compounds
-
- 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
- B01D21/0018—Separation of suspended solid particles from liquids by sedimentation provided with a pump mounted in or on a settling tank
-
- 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
- B01D21/04—Settling tanks with single outlets for the separated liquid with moving scrapers
- B01D21/06—Settling tanks with single outlets for the separated liquid with moving scrapers with rotating scrapers
-
- 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
- B01D21/245—Discharge mechanisms for the sediments
Abstract
Abstract A filter bed clarifier comprising a tank (1), which consists of an upper, cylindrical part (2) and a lower, tapered part (3) and which is provided with a centrally disposed feed pipe (11) for the liquid to be clarified. The feed pipe has an outlet leading into the tank at the top opening (7) of the circulating/mixing cone (6) disposed in the lower, tapered part of the tank. The top opening is larger than the outlet opening (12) of the feed pipe so that the sludge being dis-charged from the feed pipe draws sediment flocs from the lower part of the bed, thus causing internal circulation of the sediment. The apparatus is especially suitable for clarifying green liquor.
Fig. 1
Fig. 1
Description
~32~982 Filter bed clarifier The present invention relates to a filter bed clarifier comprising a tank which consists of an upper, cylindrical part and a lower, tapered part and which is provided with a centrally disposed feed pipe for the sludge to be clarified.
The apparatus according to the invention is suitable for separating various liquids and solids from each other and has been especially developed for separating green liquor sediment from green liquor. Green liquor is a sludge con-taining Na2C03 and Na2S, which is produced when the melt issuing from the soda recovery boiler is dissolved in water in the chemical recovery process in stock preparation. Purity of green liquor is very important in pulp mills. Higher purity provides cost savings because of a smaller size of equipment required, reduced need for lime change, less chemical losses as well as improved filtering characteristics of lime sludge.
.
Clarifiers with a filter bed have long been used in water treatment plants. Their advantages over clarifiers operating on a settling principle are, for example, a smaller size of equipment required and a higher degree of separation.
The clarifier according to the invention is based on the concept of a hydraulically fluidized filter bed, the operating principle of which is disclosed, for example, in the following article: Tesarik, J., Flow in sludge-blanket clarifiers.
urnal of the Sanitary Engineering Division, Proceedings of the ~erican Society of Civil Engineers, Vol. 93, ~o SA6, December 1967, pp. 105-120. The sludge to be introduced into 'he filter bed clarifier is flocculated by means of a polymer.
~'he filter bed binds the flocculated solids that are present in the upwardly-flowing sludge. The liquid released from the solids, i.e. the clarified liquid, is removed from the liq-~id layer formed on the upper surface of the filter bed.
~ .:.
.~,. .. ...
;D t;"~ i`N 2 A
.-.:-2 ~32~
Figure 5 of the aforesaid article shows a filter bed clari-fier comprising a tank which consists of an upper, cylindrical part and a lower, tapered part and which is provided with a centrally disposed and downwardly extending feed pipe. The lower edge of the feed cone together with the bottom of the tank form an annular discharge opening, which distributes the sludge to be fed evenly over the filtering bed. Thickened sludge is removed from the upper surface of the the bed through overflow openings disposed on the periphery of the tank. Clarifiers with hydraulically fluidized filter beds have also been disclosed in, for example, GB patent specifications ;
1437140 and 1445485.
"
The object of the invention is to provide an apparatus im-proved in comparison with the one disclosed in said article and with other known clarifiers utilizing a hydraulically fluidized filter bed. To achieve this object, the feed pipe of the clarifier according to the invention has an outlet leading to the top opening of the circulating/mixing cone (truncated conical baffle member) disposed in the tapered part of the tank, said top opening of the cone being larger than the outlet opening of said feed pipe.
~hen being discharged from the feed pipe to the circulating/
mixing cone, the sludge jet draws sediment flocs from the fluidized sediment bed above and carries them further through the top opening of the cone into the cone, where the sediment flocs are mixed with the feed jet. Because of the thus created internal circulation of the sediment, the densities of the lnfeed and the sediment bed become balanced and the consump-tion of polymer is cut down. A special circulation pump for sediment becomes unnecessary, whereby disintegration of sediment flocs in the pump is avoided.
The invention is described more in detail below, by way of e~ample, with reference to the accompanying drawings, in which -~` -P~ 2~
' ' ' :' '' ' ,' , . ;' , ' '.~ ' " , ''' . ~ .
13~ 2 :" ~ , Fig. 1 is an elevation, partially sectionalised, of an apparatus according to the invention, Fig. 2 is an enlarged sectional detail of the lower part of the apparatus of Fig. 1, and ,,..,,.' Fig. 3 is a sectional view taken along line A-A of Fig. 2.
:
The apparatus illustrated in the drawings comprises a tank 1, which has an upper, cylindrical part 2 and a lower, tapered part 3. A coaxial shaft 4, rotatable by a motor 5 disposed on top of the tank, extends through the tank. Attached to the shaft is a truncated circulating/mixing cone 6 in the form of an inverted, funnel-like baffle, which is so disposed in the lower, tapered part of the tank that its top opening 7 faces upwardly and its lower edge 8 is spaced at a small distance from the inner surface of the tapered part of the tank. The shaf~ 4 is also connected with a guide cone 9 disposed below the circulating/mixing cone 6. These cones 6, 9 form an annular opening 10 therebetween. Disposed around the shaft 4 is a pipe 11 having an outlet opening 12 at its lower end disposed in the region of the larger top opening 7 of the cir-culating/ mixing cone. The upper end 13 of the pipe 11 is connected to an inlet pipe 14 for inlet of the sludge which is to be clarified. Also connected to the shaft 4 is scraper means ~5 comprising flat rods that wipe the inner surface of the lower part when the shaft 4 rotates. At the edges of the cones 6 and 9 near the scrapers, there are sediment discharge duct members or pits 18, which interrupt the opening 10 and form channels by means of which the tank spaces 16 and 17 above and below the opening are connected to each other. The lower end of the tapered part of the tank is provlded with an opening 19 for discharging the sediment. The upper end of the _ylindrical part of the tank is provided with a discharge opening 20 for the clarified liquid. Above the top opening 7 o~ the circulating/mixing cone 6 is disposed a cone 23, which ",' :-P 5 ~1~ f E:N 2 4 4 ~3~ 2 is movable upwardly and downwardly along the surface of thefeed pipe 11, thereby opening or closing the top opening 7 of the circulating/mixing cone 6. Movements and adjustment of the cone 23 are effected by a hoisting/adjusting element 24 disposed in an upper region of the tank 1.
Internal circulation of the sediment is adjustable or con-trollable by means of the cone 23, and after a standstill of the clarifier, when a sediment bed 21 has settled in the space 16 of the cone 3, the top opening of the circulating/mixing cone 6 can be so closed that the feed flow through the outlet opening 12 of the feed pipe 11 is caused to be discharged through the annular opening 10 and further below the sediment bed 21 settled in the space 16 of the cone 3.
;, The apparatus functions as follows. The sludge to be clari-fi~d, such as green liquor, with added polymer which con-tributes to flocculation, is fed through the inlet pipe 14 to the feed pipe 11, wherefrom it is discharged through the ou~let opening 12 in the form of a jet into the cir-culating/mixiny cone 6. Therefrom the sludge, evenly dis-tributed, flows upwards through the annular opening 10 between s~id circulating/mixing cone 6 and the guide cone 9 to the enlarging annular space 16. Part of the sludge forms the fluidized filtering sediment bed 21, mainly in the cylindrical part of the tank, and another part flows downwardly as will be described more in detail the following.
When being discharged from the outlet opening 12 of the feed pipe, the sludge jet draws with it sediment flocs rrom the fluidized sediment bed 21 above and carries them into ,he circulating/mixing cone, where they become mixed with the feed jet. After being discharged from the circulating/mixing cone, ~he light flocs are raised by the flow to the sediment bed. Heavy and large flocs flow to the sediment concentration part 17 disposed below the annular opening 10, wherefrom the Po~ 2 ~32~ 9 8 sediment, either continually or intermittently, is discharged through the discharge opening 19.
In the space 16 which enlarges considerably (about 60~ up-wards, a downward flow (a so-called back eddy) is formed in the vicinity of the walls and flocs tend to settle on the walls. The rotating scraper 16 as well as the rotating movement of the cone 6 maintain the areas near the walls in a fluidized state.
: ' ",' ' , Those siediment flocs which have become too big and too dense for the velocity of the upwardly flowing sludge to fluidiæe them, flow down along the conical wall of the tank and are further guided by the scrapers to the sediment discharge pit 18, wheriefrom they flow, protected from the flow issuing from the annular opening 10, further to the sediment concentration chamber 17. The rotation of the sediment discharge pit secures even discharge of the sediment from below the bed. In the concentration part, the rotary movement of the scraper 15 maintains the sediment to be discharged uniform in quality and suitable for discharging. After flowing through the filter bed 2~, the liquid separated from the solids is removed from the liquid layer formed on top the upper surface 22 of the bed through the discharge opening 20.
: -The invention is not limited to the embodiment described above, but several variations thereof are possible within the inventive scope defined in the accompanying claims.
,' :
- '.
- .:
~ N24 ~ :; . . ~ ,. . . . .. . .. i . . . .
The apparatus according to the invention is suitable for separating various liquids and solids from each other and has been especially developed for separating green liquor sediment from green liquor. Green liquor is a sludge con-taining Na2C03 and Na2S, which is produced when the melt issuing from the soda recovery boiler is dissolved in water in the chemical recovery process in stock preparation. Purity of green liquor is very important in pulp mills. Higher purity provides cost savings because of a smaller size of equipment required, reduced need for lime change, less chemical losses as well as improved filtering characteristics of lime sludge.
.
Clarifiers with a filter bed have long been used in water treatment plants. Their advantages over clarifiers operating on a settling principle are, for example, a smaller size of equipment required and a higher degree of separation.
The clarifier according to the invention is based on the concept of a hydraulically fluidized filter bed, the operating principle of which is disclosed, for example, in the following article: Tesarik, J., Flow in sludge-blanket clarifiers.
urnal of the Sanitary Engineering Division, Proceedings of the ~erican Society of Civil Engineers, Vol. 93, ~o SA6, December 1967, pp. 105-120. The sludge to be introduced into 'he filter bed clarifier is flocculated by means of a polymer.
~'he filter bed binds the flocculated solids that are present in the upwardly-flowing sludge. The liquid released from the solids, i.e. the clarified liquid, is removed from the liq-~id layer formed on the upper surface of the filter bed.
~ .:.
.~,. .. ...
;D t;"~ i`N 2 A
.-.:-2 ~32~
Figure 5 of the aforesaid article shows a filter bed clari-fier comprising a tank which consists of an upper, cylindrical part and a lower, tapered part and which is provided with a centrally disposed and downwardly extending feed pipe. The lower edge of the feed cone together with the bottom of the tank form an annular discharge opening, which distributes the sludge to be fed evenly over the filtering bed. Thickened sludge is removed from the upper surface of the the bed through overflow openings disposed on the periphery of the tank. Clarifiers with hydraulically fluidized filter beds have also been disclosed in, for example, GB patent specifications ;
1437140 and 1445485.
"
The object of the invention is to provide an apparatus im-proved in comparison with the one disclosed in said article and with other known clarifiers utilizing a hydraulically fluidized filter bed. To achieve this object, the feed pipe of the clarifier according to the invention has an outlet leading to the top opening of the circulating/mixing cone (truncated conical baffle member) disposed in the tapered part of the tank, said top opening of the cone being larger than the outlet opening of said feed pipe.
~hen being discharged from the feed pipe to the circulating/
mixing cone, the sludge jet draws sediment flocs from the fluidized sediment bed above and carries them further through the top opening of the cone into the cone, where the sediment flocs are mixed with the feed jet. Because of the thus created internal circulation of the sediment, the densities of the lnfeed and the sediment bed become balanced and the consump-tion of polymer is cut down. A special circulation pump for sediment becomes unnecessary, whereby disintegration of sediment flocs in the pump is avoided.
The invention is described more in detail below, by way of e~ample, with reference to the accompanying drawings, in which -~` -P~ 2~
' ' ' :' '' ' ,' , . ;' , ' '.~ ' " , ''' . ~ .
13~ 2 :" ~ , Fig. 1 is an elevation, partially sectionalised, of an apparatus according to the invention, Fig. 2 is an enlarged sectional detail of the lower part of the apparatus of Fig. 1, and ,,..,,.' Fig. 3 is a sectional view taken along line A-A of Fig. 2.
:
The apparatus illustrated in the drawings comprises a tank 1, which has an upper, cylindrical part 2 and a lower, tapered part 3. A coaxial shaft 4, rotatable by a motor 5 disposed on top of the tank, extends through the tank. Attached to the shaft is a truncated circulating/mixing cone 6 in the form of an inverted, funnel-like baffle, which is so disposed in the lower, tapered part of the tank that its top opening 7 faces upwardly and its lower edge 8 is spaced at a small distance from the inner surface of the tapered part of the tank. The shaf~ 4 is also connected with a guide cone 9 disposed below the circulating/mixing cone 6. These cones 6, 9 form an annular opening 10 therebetween. Disposed around the shaft 4 is a pipe 11 having an outlet opening 12 at its lower end disposed in the region of the larger top opening 7 of the cir-culating/ mixing cone. The upper end 13 of the pipe 11 is connected to an inlet pipe 14 for inlet of the sludge which is to be clarified. Also connected to the shaft 4 is scraper means ~5 comprising flat rods that wipe the inner surface of the lower part when the shaft 4 rotates. At the edges of the cones 6 and 9 near the scrapers, there are sediment discharge duct members or pits 18, which interrupt the opening 10 and form channels by means of which the tank spaces 16 and 17 above and below the opening are connected to each other. The lower end of the tapered part of the tank is provlded with an opening 19 for discharging the sediment. The upper end of the _ylindrical part of the tank is provided with a discharge opening 20 for the clarified liquid. Above the top opening 7 o~ the circulating/mixing cone 6 is disposed a cone 23, which ",' :-P 5 ~1~ f E:N 2 4 4 ~3~ 2 is movable upwardly and downwardly along the surface of thefeed pipe 11, thereby opening or closing the top opening 7 of the circulating/mixing cone 6. Movements and adjustment of the cone 23 are effected by a hoisting/adjusting element 24 disposed in an upper region of the tank 1.
Internal circulation of the sediment is adjustable or con-trollable by means of the cone 23, and after a standstill of the clarifier, when a sediment bed 21 has settled in the space 16 of the cone 3, the top opening of the circulating/mixing cone 6 can be so closed that the feed flow through the outlet opening 12 of the feed pipe 11 is caused to be discharged through the annular opening 10 and further below the sediment bed 21 settled in the space 16 of the cone 3.
;, The apparatus functions as follows. The sludge to be clari-fi~d, such as green liquor, with added polymer which con-tributes to flocculation, is fed through the inlet pipe 14 to the feed pipe 11, wherefrom it is discharged through the ou~let opening 12 in the form of a jet into the cir-culating/mixiny cone 6. Therefrom the sludge, evenly dis-tributed, flows upwards through the annular opening 10 between s~id circulating/mixing cone 6 and the guide cone 9 to the enlarging annular space 16. Part of the sludge forms the fluidized filtering sediment bed 21, mainly in the cylindrical part of the tank, and another part flows downwardly as will be described more in detail the following.
When being discharged from the outlet opening 12 of the feed pipe, the sludge jet draws with it sediment flocs rrom the fluidized sediment bed 21 above and carries them into ,he circulating/mixing cone, where they become mixed with the feed jet. After being discharged from the circulating/mixing cone, ~he light flocs are raised by the flow to the sediment bed. Heavy and large flocs flow to the sediment concentration part 17 disposed below the annular opening 10, wherefrom the Po~ 2 ~32~ 9 8 sediment, either continually or intermittently, is discharged through the discharge opening 19.
In the space 16 which enlarges considerably (about 60~ up-wards, a downward flow (a so-called back eddy) is formed in the vicinity of the walls and flocs tend to settle on the walls. The rotating scraper 16 as well as the rotating movement of the cone 6 maintain the areas near the walls in a fluidized state.
: ' ",' ' , Those siediment flocs which have become too big and too dense for the velocity of the upwardly flowing sludge to fluidiæe them, flow down along the conical wall of the tank and are further guided by the scrapers to the sediment discharge pit 18, wheriefrom they flow, protected from the flow issuing from the annular opening 10, further to the sediment concentration chamber 17. The rotation of the sediment discharge pit secures even discharge of the sediment from below the bed. In the concentration part, the rotary movement of the scraper 15 maintains the sediment to be discharged uniform in quality and suitable for discharging. After flowing through the filter bed 2~, the liquid separated from the solids is removed from the liquid layer formed on top the upper surface 22 of the bed through the discharge opening 20.
: -The invention is not limited to the embodiment described above, but several variations thereof are possible within the inventive scope defined in the accompanying claims.
,' :
- '.
- .:
~ N24 ~ :; . . ~ ,. . . . .. . .. i . . . .
Claims (10)
1. A filter bed clarifier comprising a tank, which consists of an upper, cylindrical part and a lower, tapered part and which is provided with a centrally disposed feed pipe for the liquid to be clarified, characterized in that the feed pipe has an outlet leading to the top opening of a truncated circulating/mixing conical member or cone disposed in the lower, tapered part of the tank, said top opening being larger than the outlet opening of the feed pipe.
2. An apparatus as claimed in claim 1, characterized in that an annular opening is formed between the lower edge of the circulating/mixing cone and a tapered plate disposed in the lower, tapered part of the tank.
3. An apparatus as claimed in claim 2, characterized in that near the annular opening is disposed at least one sediment discharge duct or pit, which interrupts said opening and which connects the tank spaces above and below the opening to each other.
4. An apparatus as claimed in claim 2, characterized in that above the annular opening at least one scraper is disposed displaceable along the surface of the lower, tapered part of the tank.
5. An apparatus as claimed in claim 2, characterized in that at least one scraper is disposed below the annular opening and displaceable along the surface of the lower, tapered part of the tank.
6. An apparatus as claimed in any of the claims 1 to 5, characterized in that the circulating/mixing cone is rotatable.
7. An apparatus as claimed in claim 4 or 5, characterized in that the circulating/mixing cone is attached to the shaft which rotates said at least onescraper.
8. An apparatus as claimed in any one of claims 1 - 5, characterized in that, at the lower end of the tapered part of the tank a sediment discharge opening is disposed.
9. An apparatus as claimed in any one of claims 1 - 5, characterized in that, at the upper end of the cylindrical part of the tank is disposed a discharge opening for the clarified liquid.
10. An apparatus as claimed in any one of claims 1 - 5, characterized in that, above the top opening of the circulating/mixing cone a cone is disposedwhich is displaceable upwardly and downwardly along the feed pipe.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI873971A FI81269C (en) | 1987-09-14 | 1987-09-14 | CLOSED CLARCHES. |
| FI873971 | 1987-09-14 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1325982C true CA1325982C (en) | 1994-01-11 |
Family
ID=8525047
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000577204A Expired - Fee Related CA1325982C (en) | 1987-09-14 | 1988-09-13 | Filter bed clarifier |
Country Status (8)
| Country | Link |
|---|---|
| US (1) | US4871459A (en) |
| JP (1) | JPH01107813A (en) |
| CA (1) | CA1325982C (en) |
| ES (1) | ES2010360A6 (en) |
| FI (1) | FI81269C (en) |
| FR (1) | FR2620349B1 (en) |
| PT (1) | PT88496B (en) |
| SE (1) | SE464852B (en) |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5120436A (en) * | 1991-03-21 | 1992-06-09 | Reichner Thomas W | Liquid clarification by effecting cohesion of solids |
| US5433862A (en) * | 1992-08-24 | 1995-07-18 | Technology Finance Corporation (Proprietary) Limited | Process for treating a suspension of solid particles in a carrier liquid |
| US5478468A (en) * | 1993-09-10 | 1995-12-26 | Sumitomo Heavy Industries, Ltd. | Coagulating sedimentation processing apparatus |
| US5589064A (en) * | 1994-10-24 | 1996-12-31 | Elmaleh; Samuel | Apparatus for liquid solid separation of liquid effluents or wastewater |
| US6092671A (en) * | 1998-10-02 | 2000-07-25 | Chicago Bridge And Iron Company | Liquid clarification tank |
| KR100775977B1 (en) | 2005-05-18 | 2007-11-15 | 고등기술연구원연구조합 | Solid-liquid seperation and filteration apparatus |
| US8152998B2 (en) * | 2010-05-28 | 2012-04-10 | Ashbrook Simon-Hartley, LP | Screenless granular media filters and methods of use |
| US8715498B2 (en) | 2011-02-09 | 2014-05-06 | Tervita Corporation | System and apparatus for treating well flow-back and produced water or other wastewater |
| WO2017007307A1 (en) * | 2015-07-03 | 2017-01-12 | Paques I.P. B.V. | Apparatus and method for purification of a fluid by means of a filter bed |
| JP6269635B2 (en) * | 2015-11-02 | 2018-01-31 | 栗田工業株式会社 | Precipitation tank and its operation method |
| CN109289318A (en) * | 2018-10-30 | 2019-02-01 | 贵州兴贵环保工程有限公司 | Water quality silt multistage filtering separator |
| CN112933729A (en) * | 2021-01-28 | 2021-06-11 | 南京可常道商贸有限公司 | High whiteness sanitary towel thick liquid concentrator |
| SE2150525A1 (en) * | 2021-04-26 | 2022-10-27 | Valmet Oy | Mixing assembly and method for controlling mixing of green liquor and a flocculation agent |
| CN114985093B (en) * | 2022-06-14 | 2024-04-05 | 山东和创瑞思环保科技有限公司 | Cyclone separation high shear |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US400807A (en) * | 1889-04-02 | Apparatus for malting grain | ||
| US196259A (en) * | 1877-10-16 | Improvement in apparatus for continuous decantation in the ammonia-soda process | ||
| DE1070595B (en) * | 1959-12-10 | |||
| US958832A (en) * | 1909-04-07 | 1910-05-24 | Hezekiah Russell | Water-softening apparatus. |
| US1526197A (en) * | 1923-08-18 | 1925-02-10 | Ahlqvist Harald | Clarification process and apparatus |
| US1943330A (en) * | 1929-09-25 | 1934-01-16 | Lafayette M Hughes | Method and apparatus for the intertreatment of liquid and solid materials |
| US2230386A (en) * | 1937-08-12 | 1941-02-04 | American Centrifugal Corp | Separation of solids from liquids |
| US2422258A (en) * | 1944-06-09 | 1947-06-17 | Graver Tank & Mfg Co Inc | Liquid treatment with auxiliary flow of liquid to suspend and preserve a sludge blanket |
| US2523523A (en) * | 1946-11-22 | 1950-09-26 | Worthington Pump & Mach Corp | Apparatus for water purification |
| US2793186A (en) * | 1954-01-08 | 1957-05-21 | Ca Nat Research Council | Apparatus for classifying or settling fluid suspensions |
| US3250394A (en) * | 1963-05-03 | 1966-05-10 | Cities Service Athabasca Inc | Flotation apparatus |
| FR1516848A (en) * | 1966-12-15 | 1968-02-05 | liquid purifier loaded with solid particles | |
| US4197201A (en) * | 1976-03-03 | 1980-04-08 | Rederiaktiebolaget Nordstjernan | Apparatus for the filtration of a suspension or emulsion |
-
1987
- 1987-09-14 FI FI873971A patent/FI81269C/en not_active IP Right Cessation
-
1988
- 1988-09-08 US US07/241,452 patent/US4871459A/en not_active Expired - Fee Related
- 1988-09-12 SE SE8803203A patent/SE464852B/en not_active IP Right Cessation
- 1988-09-13 FR FR888811932A patent/FR2620349B1/en not_active Expired - Fee Related
- 1988-09-13 CA CA000577204A patent/CA1325982C/en not_active Expired - Fee Related
- 1988-09-14 JP JP63231413A patent/JPH01107813A/en active Granted
- 1988-09-14 PT PT88496A patent/PT88496B/en not_active IP Right Cessation
- 1988-09-14 ES ES8802793A patent/ES2010360A6/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01107813A (en) | 1989-04-25 |
| JPH0336561B2 (en) | 1991-05-31 |
| SE8803203L (en) | 1989-03-15 |
| FI81269C (en) | 1990-10-10 |
| PT88496B (en) | 1993-09-30 |
| ES2010360A6 (en) | 1989-11-01 |
| FR2620349B1 (en) | 1992-02-07 |
| FI873971A0 (en) | 1987-09-14 |
| FR2620349A1 (en) | 1989-03-17 |
| FI81269B (en) | 1990-06-29 |
| FI873971A (en) | 1989-03-15 |
| SE8803203D0 (en) | 1988-09-12 |
| PT88496A (en) | 1989-07-31 |
| US4871459A (en) | 1989-10-03 |
| SE464852B (en) | 1991-06-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1325982C (en) | Filter bed clarifier | |
| US4054514A (en) | Sedimentation apparatus with flocculating feed well | |
| CA1085070A (en) | Thickening device and method | |
| US4142970A (en) | Method and apparatus for mechanically and chemically treating liquids | |
| US4146471A (en) | Liquid clarification apparatus and method | |
| EP2508483B1 (en) | Waste water treatment equipment | |
| US4999115A (en) | Method and apparatus for use in separating solids from liquids | |
| US4579655A (en) | Apparatus for treating water by flocculation and/or crystalline precipitation, settling and sludge recycling | |
| US2353358A (en) | Precipitation and coagulation | |
| EP0971856B1 (en) | Three zone dissolved air flotation clarifier with improved efficiency | |
| US4603000A (en) | Process and apparatus for flocculating and clarifying a solid-liquid slurry | |
| EA004962B1 (en) | Method and apparatus for clarifying and/or thickening a slurry | |
| CA1114969A (en) | Flocculant distributor means for feedwell | |
| EA004972B1 (en) | Method and apparatus for clarifying a slurry | |
| EP0016690B1 (en) | Apparatus for separating solids from suspensions in a liquid influent | |
| US2352772A (en) | Treatment of impure liquids | |
| US4009106A (en) | Clarifier with overflow scum removal | |
| US3349030A (en) | Process and apparatus for the clarification treatment of solids-carrying liquids | |
| US2488851A (en) | Sugar juice treatment | |
| IE55715B1 (en) | Clarifier | |
| CN101328004B (en) | Flocculating concentration apparatus in sludge treatment | |
| US2411390A (en) | Liquid treatment | |
| US20030155306A1 (en) | Apparatus and method for the treatment of a contaminated fluid | |
| CA2165793A1 (en) | High capacity single tank water clarification system | |
| US2528879A (en) | Clarifying apparatus |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |