NO152126B - PROCEDURE AND DEVICE FOR DRAINAGE OF SLAM - Google Patents
PROCEDURE AND DEVICE FOR DRAINAGE OF SLAM Download PDFInfo
- Publication number
- NO152126B NO152126B NO810336A NO810336A NO152126B NO 152126 B NO152126 B NO 152126B NO 810336 A NO810336 A NO 810336A NO 810336 A NO810336 A NO 810336A NO 152126 B NO152126 B NO 152126B
- Authority
- NO
- Norway
- Prior art keywords
- ramp
- sludge
- belt
- particles
- transport
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 13
- 239000010802 sludge Substances 0.000 claims description 50
- 239000002245 particle Substances 0.000 claims description 24
- 239000007787 solid Substances 0.000 claims description 17
- 239000007788 liquid Substances 0.000 claims description 12
- 230000000694 effects Effects 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- 238000005056 compaction Methods 0.000 claims description 5
- 238000005096 rolling process Methods 0.000 claims description 5
- 238000004140 cleaning Methods 0.000 claims description 2
- 238000010008 shearing Methods 0.000 claims description 2
- 239000000463 material Substances 0.000 description 5
- 238000005189 flocculation Methods 0.000 description 3
- 230000016615 flocculation Effects 0.000 description 3
- 238000005188 flotation Methods 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000000701 coagulant Substances 0.000 description 1
- 230000001112 coagulating effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000008394 flocculating agent Substances 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 230000008719 thickening Effects 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D33/00—Filters with filtering elements which move during the filtering operation
- B01D33/04—Filters with filtering elements which move during the filtering operation with filtering bands or the like supported on cylinders which are impervious for filtering
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D33/00—Filters with filtering elements which move during the filtering operation
- B01D33/44—Regenerating the filter material in the filter
- B01D33/46—Regenerating the filter material in the filter by scrapers, brushes nozzles or the like acting on the cake-side of the filtering element
- B01D33/466—Regenerating the filter material in the filter by scrapers, brushes nozzles or the like acting on the cake-side of the filtering element scrapers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D33/00—Filters with filtering elements which move during the filtering operation
- B01D33/70—Filters with filtering elements which move during the filtering operation having feed or discharge devices
- B01D33/74—Filters with filtering elements which move during the filtering operation having feed or discharge devices for discharging filtrate
- B01D33/742—Filters with filtering elements which move during the filtering operation having feed or discharge devices for discharging filtrate containing fixed liquid displacement elements or cores
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Treatment Of Sludge (AREA)
- Filtration Of Liquid (AREA)
- Sink And Installation For Waste Water (AREA)
- Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
Description
Oppfinnelsen vedrører en fremgangsmåte og en innretning for avvanning av slam, særlig aktivert slam. The invention relates to a method and a device for dewatering sludge, in particular activated sludge.
Man har lenge fortykket aktivert slam ved å la det gå gjennom Activated sludge has long been thickened by letting it pass through
en sedimenteringstank med en oppholdstid på rundt 24 timer. En slik teknikk, i tillegg til at den er tidkrevende og utstyrs-krevende, har den ulempe at det fortykkede slam vil ha en faststoff konsentrasjon på bare 1,5-2 vekt-%. a sedimentation tank with a residence time of around 24 hours. Such a technique, in addition to being time-consuming and equipment-intensive, has the disadvantage that the thickened sludge will have a solids concentration of only 1.5-2% by weight.
For å oppnå høyere faststoffinnhold i det konsentrerte slam, To achieve a higher solids content in the concentrated sludge,
har det vært foreslått ulike metoder med bruk av avansert utstyr, så som fIotasjonsutstyr, hvor suspenderte faststoffer i slammet, bringes til overflaten ved hjelp av små gassbobler som tilveiebringes elektrolytisk. Slikt fIotasjonsutstyr er effek-tivt med hensyn til å fjerne vann fra slammet, slik at det konsentrerte slam vil ha rundt 5 vekt-% faststoff. Metoden er imidlertid forbundet med flere ulemper. Utstyret er dyrt i an-skaffelse og vedlikehold, og prosessomkostningene høye. different methods have been proposed with the use of advanced equipment, such as flotation equipment, where suspended solids in the sludge are brought to the surface using small gas bubbles that are produced electrolytically. Such flotation equipment is effective in removing water from the sludge, so that the concentrated sludge will have around 5% by weight of solids. However, the method is associated with several disadvantages. The equipment is expensive to acquire and maintain, and the processing costs are high.
Foreliggende oppfinnelse bygger på et utstrakt forsøksprogram med den hensikt å finne en fremgangsmåte for fortykking av slam til en konsentrasjon på rundt 5 vekt-% faststoff eller mer, under utnyttelse av enkelt utstyr og på en økonomisk måte. The present invention is based on an extensive experimental program with the aim of finding a method for thickening sludge to a concentration of around 5% by weight of solids or more, using simple equipment and in an economical way.
Oppfinnelsen tar utgangspunkt i en fremgangsmåte henholdsvis en innretning som muliggjør en avvanning av slampartikler som fore-ligger som en flokkingsstruktur tilveiebragt ved bruk av koagu-lerende eller flokkulerende midler. Det vil være mulig å redu-sere bruken av slike meget dyre midler ved å tilveiebringe en meget ømtålig flokkuleringsstruktur og tillate denne å gå meget varsomt over på et løpende, porøst belte, hvorigjennom vann fra slammet kan dreneres. Ifølge oppfinnelsen foreslås det derfor en fremgangsmåte ved avvanning av slam, hvor slammet plasseres på et løpende, porøst transportbelte for å tillate fri væskedrenering under transporten, idet drenerte faststoffer fjernes fra transportbeltet ved transportstrekningens utgangsende, og det som kjennetegner fremgangsmåten ifølge oppfinnelsen er at før det når utgangsenden, hemmes slammet i å forlate beltet og påvirkes for oppbygging mot en rampe, hvorved det tilveiebringes en bakoverrettet rullebevegelse av slampartikler på rampen som i sin tur gir partiklene en skjærevirkning, hvorved innfanget væske frigjøres fra mellomrommet mellom partiklene og en øket kompaktering tillates, før slammet strømmer over rampen for fjerning. The invention is based on a method or a device which enables the dewatering of sludge particles which are present as a flocculation structure provided by the use of coagulating or flocculating agents. It will be possible to reduce the use of such very expensive agents by providing a very delicate flocculation structure and allowing this to pass very carefully onto a running, porous belt, through which water from the sludge can be drained. According to the invention, a method for dewatering sludge is therefore proposed, where the sludge is placed on a running, porous conveyor belt to allow free liquid drainage during transport, as drained solids are removed from the conveyor belt at the exit end of the transport section, and what characterizes the method according to the invention is that before the when it reaches the exit end, the sludge is inhibited from leaving the belt and is influenced to build up against a ramp, thereby providing a backward rolling movement of sludge particles on the ramp which in turn gives the particles a shearing effect, whereby trapped liquid is released from the space between the particles and an increased compaction is allowed, before the sludge flows over the ramp for removal.
Ifølge oppfinnelsen foreslås det også en innretning for avvanning av slam, innbefattende et bevegbart, porøst transportbelte, en anordning for plassering av slam på beltet ved inn-gangsenden til en transportstrekning av beltet, slik at væske kan drenere gjennom beltet, og en anordning for fjerning av drenerte faststoffer fra beltet ved transportstrekningens utgangsende, og det som kjennetegner innretningen ifølge oppfinnelsen er at en rampe er anordnet over beltet før utgangsenden, hvilken rampe går oppover fra belteflaten for derved å begrense slammets foroverrettede bevegelse og således bringe slammet i å forlate beltet og gå opp på rampen, idet rampen er regnet til å gi slampartiklene en bakoverrettet rullebevegelse på rampen som i sin tur gir partiklene en skjærevirkning, hvorved innfanget væske frigjøres fra mellomrommet mellom partiklene og en øket kompaktering tillates, før slammet strømmer over rampen for fjerning. According to the invention, a device for dewatering sludge is also proposed, including a movable, porous conveyor belt, a device for placing sludge on the belt at the entrance end of a transport section of the belt, so that liquid can drain through the belt, and a device for removal of drained solids from the belt at the exit end of the transport section, and what characterizes the device according to the invention is that a ramp is arranged above the belt before the exit end, which ramp goes up from the belt surface to thereby limit the forward movement of the sludge and thus cause the sludge to leave the belt and go up the ramp, as the ramp is calculated to give the sludge particles a backward rolling movement on the ramp which in turn gives the particles a cutting effect, whereby trapped liquid is released from the space between the particles and an increased compaction is allowed, before the sludge flows over the ramp for removal.
Fra US-PS 3984329 er det kjent en innretning hvor det ikke benyttes en rampe, men bare strømningsbrytere som gir en slags plogvirkning på slammet. Dette er noe som ikke vil kunne tillates i forbindelse med en litt ømtålig flokkingsstruktur, og ikke i noe tilfelle vil man kunne få den ønskede bakoverrettede rullevirkning av slampartiklene. From US-PS 3984329, a device is known where a ramp is not used, but only flow switches which provide a kind of plowing effect on the sludge. This is something that will not be allowed in connection with a somewhat delicate flocculation structure, and in no case will you be able to get the desired backward rolling effect of the sludge particles.
Fra US-PS 2457018 er det kjent en vibrerende sikt med avstands-stoppere som gir en oppbygging av materialet. Vibreringen i sikten bevirker at partiklene kan gå opp den lett skråstilte sikt, men denne vibrasjonsvirkning egner seg ikke for en ømtålig flokkingsstruktur. Det benyttes heller ingen reell rampe som slammet går opp på fra et belte. From US-PS 2457018, a vibrating sieve with distance stoppers is known which provides a build-up of the material. The vibration in the sieve means that the particles can go up the slightly inclined sieve, but this vibration effect is not suitable for a delicate flocking structure. No real ramp is used either, on which the sludge goes up from a belt.
Oppfinnelsen skal forklares nærmere under henvisning til tegningene, hvor: Figur 1 viser et skjematisk vertikalsnitt gjennom en innretning, The invention shall be explained in more detail with reference to the drawings, where: Figure 1 shows a schematic vertical section through a device,
figur 2 viser et forstørret utsnitt av innretningen i figur 1, figure 2 shows an enlarged section of the device in figure 1,
og and
figur 3 viser et grunnriss av den del av innretningen som er Figure 3 shows a floor plan of the part of the device that is
vist i figur 2. shown in Figure 2.
Den på tegningene viste innretning innbefatter et gitterforriiet transportbelte 10 som drives av eller er lagt rundt flere ruller 11,12 og 13. Slam som skal behandles plasseres på det bevegede beltet 10 over en rampe 14 som mates fra en tank 15. The device shown in the drawings includes a grid-lined conveyor belt 10 which is driven by or is placed around several rollers 11, 12 and 13. Sludge to be treated is placed on the moving belt 10 above a ramp 14 which is fed from a tank 15.
Under beltet 10 er det anbragt et par styreplater 16 og 17. Disse er beregnet til å samle opp vann som går ned gjennom beltet 10 og styrer vannet til en samlebeholder 18. Man vil se at det vann som går fra styreplaten 16 og 17 og ned i beholderen 18 under dette vil måtte gå gjennom beltet 10 i et returavsnitt av dette, melom rullene 12 og 11, og vannet vil derved vaske beltet og fjerne eventuelt restmateriale. A pair of guide plates 16 and 17 are placed under the belt 10. These are designed to collect water that goes down through the belt 10 and direct the water to a collection container 18. You will see that the water that goes from the guide plates 16 and 17 and down in the container 18 below this will have to pass through the belt 10 in a return section of this, between the rollers 12 and 11, and the water will thereby wash the belt and remove any residual material.
En samlebeholder 20 er anordnet under nedstrømenden til beltets transportstrekning for oppsamling av avvannede faststoffer. Hensiktsmessig benyttes en skruetransportør 21 for fjerning av faststoffene fra beholderen, men man kan naturligvis også benytte en annen egnet innretning her. A collection container 20 is arranged below the downstream end of the belt's transport section for collecting dewatered solids. Appropriately, a screw conveyor 21 is used for removing the solids from the container, but you can of course also use another suitable device here.
En rampeflate 25 er anordnet ved den nevnte nedstrømende av beltets 10 transportstrekning, og en del 26 (figur 2) av rampeflaten er plassert slik at den virker som et skraperblad for A ramp surface 25 is arranged at the mentioned downstream of the belt 10 transport section, and a part 26 (figure 2) of the ramp surface is positioned so that it acts as a scraper blade for
rengjøring av beltet. Det er anordnet faste sideplater 27 cleaning the belt. There are fixed side plates 27
for tilbakeholding av materiale under dettes oppsamling på rampeflaten 25. for retention of material during its collection on the ramp surface 25.
Når innretningen er i drift mates slam kontinuerlig fra tanken 15 ned på beltet 10 og føres av dette mens væske fritt kan When the device is in operation, sludge is continuously fed from the tank 15 onto the belt 10 and carried by this, while liquid can freely
dreneres gjennom beltet 10. Ved beltets transportstreknings nedstrømsende må det avvannede slam gå opp på rampeflaten 25 før slammet kan gå over rampeflatens øvre ende og samles opp i beholderen 20. Rampeflaten bevirker en oppbygging av materi-alpartikler i slammet, og det skjer en tilbakeføring mot beltet, som antydet med pilen 30. Dette bevirker en relativ bevegelse mellom faststoffpartiklene og det oppstår en skjærevirkning som frigjør innfanget væske og således muliggjør en større kompaktering. Partiklene på rampen vil dessuten utøve en vektbelastning på de nederste partiklene, og det fremføre materiale på beltet vil utøve et kontinuerlig trykk. Disse faktorer tillater en ytterligere betydelig væskedrenering fra slammet, slik at slam- is drained through the belt 10. At the downstream end of the belt's transport section, the dewatered sludge must go up onto the ramp surface 25 before the sludge can pass over the upper end of the ramp surface and be collected in the container 20. The ramp surface causes a build-up of material particles in the sludge, and there is a return towards the belt, as indicated by arrow 30. This causes a relative movement between the solid particles and a cutting effect occurs which releases trapped liquid and thus enables a greater compaction. The particles on the ramp will also exert a weight load on the lower particles, and the advancing material on the belt will exert a continuous pressure. These factors allow a further significant liquid drainage from the sludge, so that sludge
i met til slutt vil ha en faststoffkonsentrasjon på 6,5 vekt-% eller mer. in the met will eventually have a solids concentration of 6.5 wt% or more.
Man har ved forsøk funnet at rampeflatens skråvinkel bestemmer avvanningseffektiviteten i dette område. I hovedsaken vil fast-stoffkonsentrasjonen være proposjonal med rampens vinkel. It has been found in experiments that the slope angle of the ramp surface determines the dewatering efficiency in this area. In the main, the solids concentration will be proportional to the angle of the ramp.
I utførelseseksempelet er rampeflaten vist plassert ved transportstrekningens utgangsende, men den kan også eventuelt plasseres et sted i selve transportstrekningen, og man kan benytte I mer enn en slik rampeflate langs transportstrekningen. In the design example, the ramp surface is shown placed at the exit end of the transport section, but it can also optionally be placed somewhere in the transport section itself, and more than one such ramp surface can be used along the transport section.
I figur 3 er det vist hvordan en ytterligere hindring for den frie foroverrettede bevegelse av slammet kan tilveiebringes ved hjelp av V-formede elementer 31 som er plassert på rampeflaten 5 for å bevirke en sideinnsnevring av slampartiklene ettersom disse går opp på rampen. In Figure 3 it is shown how a further obstacle to the free forward movement of the sludge can be provided by means of V-shaped elements 31 which are placed on the ramp surface 5 to cause a lateral narrowing of the sludge particles as they go up the ramp.
I noen tilfeller kan dette medføre forbedringer, særlig i de tilfeller hvor den frie væskedrenering fra slammet gjennom beltet ikke uten videre oppnås under transporten. In some cases, this can lead to improvements, particularly in cases where free liquid drainage from the sludge through the belt is not easily achieved during transport.
Claims (9)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8003495A GB2068761B (en) | 1980-02-01 | 1980-02-01 | Method and apparatus for dewatering sludge |
Publications (3)
Publication Number | Publication Date |
---|---|
NO810336L NO810336L (en) | 1981-08-03 |
NO152126B true NO152126B (en) | 1985-04-29 |
NO152126C NO152126C (en) | 1985-08-28 |
Family
ID=10511066
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
NO810336A NO152126C (en) | 1980-02-01 | 1981-01-30 | PROCEDURE AND DEVICE FOR WATER DRAINAGE |
Country Status (13)
Country | Link |
---|---|
JP (1) | JPS56124409A (en) |
AU (1) | AU539433B2 (en) |
CA (1) | CA1163571A (en) |
DE (1) | DE3101105A1 (en) |
FR (1) | FR2475031B1 (en) |
GB (1) | GB2068761B (en) |
HK (1) | HK77087A (en) |
IT (1) | IT1135235B (en) |
NL (1) | NL188327C (en) |
NO (1) | NO152126C (en) |
SE (2) | SE442592B (en) |
SG (1) | SG25487G (en) |
ZA (1) | ZA81329B (en) |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4731188A (en) * | 1986-04-03 | 1988-03-15 | Ashbrook-Simon-Hartley | Adjustable ramp for dewatering device |
GB8909463D0 (en) * | 1989-04-26 | 1989-06-14 | Hartley Simon Ltd | Apparatus for dewatering sludge |
GB2232611B (en) * | 1989-06-02 | 1992-10-14 | D & C Ltd | Horizontal belt vacuum filtration apparatus |
ATE81304T1 (en) * | 1989-06-30 | 1992-10-15 | Hoppe & Partner | PROCESS AND EQUIPMENT FOR PRE-THICKENING MUD. |
AU2002344431A1 (en) * | 2002-02-15 | 2003-09-04 | Arao City | Gravity type thickener, gravity type thickening method, coagulant adding device, and coagulant adding method |
CN116537744B (en) * | 2023-07-07 | 2023-09-08 | 山东省路桥集团有限公司 | Drilling machine blowdown mechanism for road construction |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB754168A (en) * | 1953-06-25 | 1956-08-01 | Lukens Steel Co | Rotary table filter |
GB909512A (en) * | 1960-03-22 | 1962-10-31 | Arthur Andrew Holland | Endless belt filter |
SE365122B (en) * | 1972-04-13 | 1974-03-18 | Nordstjernan Rederi Ab | |
NL176054C (en) * | 1974-02-27 | 1985-02-18 | Bellmer Geb Kg Maschf | FILTER EQUIPMENT. |
GB1602677A (en) * | 1978-05-25 | 1981-11-11 | Hartley Simon Ltd | Sludge thickening |
-
1980
- 1980-02-01 GB GB8003495A patent/GB2068761B/en not_active Expired
-
1981
- 1981-01-15 DE DE19813101105 patent/DE3101105A1/en active Granted
- 1981-01-19 ZA ZA00810329A patent/ZA81329B/en unknown
- 1981-01-19 CA CA000368798A patent/CA1163571A/en not_active Expired
- 1981-01-26 NL NLAANVRAGE8100357,A patent/NL188327C/en not_active IP Right Cessation
- 1981-01-29 AU AU66736/81A patent/AU539433B2/en not_active Expired
- 1981-01-30 SE SE8100710A patent/SE442592B/en not_active IP Right Cessation
- 1981-01-30 NO NO810336A patent/NO152126C/en not_active IP Right Cessation
- 1981-01-30 FR FR8101852A patent/FR2475031B1/en not_active Expired
- 1981-01-30 JP JP1372581A patent/JPS56124409A/en active Pending
- 1981-01-30 IT IT19418/81A patent/IT1135235B/en active
- 1981-01-30 SE SE8100710D patent/SE8100710L/en not_active Application Discontinuation
-
1987
- 1987-03-12 SG SG254/87A patent/SG25487G/en unknown
- 1987-10-15 HK HK770/87A patent/HK77087A/en not_active IP Right Cessation
Also Published As
Publication number | Publication date |
---|---|
SE8100710L (en) | 1981-08-02 |
AU6673681A (en) | 1981-08-06 |
NL188327B (en) | 1992-01-02 |
NO810336L (en) | 1981-08-03 |
DE3101105C2 (en) | 1987-07-23 |
FR2475031A1 (en) | 1981-08-07 |
IT8119418A0 (en) | 1981-01-30 |
NL188327C (en) | 1992-06-01 |
HK77087A (en) | 1987-10-23 |
AU539433B2 (en) | 1984-09-27 |
FR2475031B1 (en) | 1986-05-09 |
NO152126C (en) | 1985-08-28 |
GB2068761A (en) | 1981-08-19 |
SE442592B (en) | 1986-01-20 |
JPS56124409A (en) | 1981-09-30 |
DE3101105A1 (en) | 1981-11-19 |
ZA81329B (en) | 1982-02-24 |
SG25487G (en) | 1987-09-18 |
GB2068761B (en) | 1984-04-26 |
NL8100357A (en) | 1981-09-01 |
CA1163571A (en) | 1984-03-13 |
IT1135235B (en) | 1986-08-20 |
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Legal Events
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MK1K | Patent expired |
Free format text: EXPIRED IN JANUARY 2001 |
|
MM1K | Lapsed by not paying the annual fees |
Free format text: LAPSED IN JANUARY 2001 |