AU629069B2 - Waste water filtration - Google Patents

Waste water filtration Download PDF

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Publication number
AU629069B2
AU629069B2 AU67035/90A AU6703590A AU629069B2 AU 629069 B2 AU629069 B2 AU 629069B2 AU 67035/90 A AU67035/90 A AU 67035/90A AU 6703590 A AU6703590 A AU 6703590A AU 629069 B2 AU629069 B2 AU 629069B2
Authority
AU
Australia
Prior art keywords
waste water
filter
filtration
vessel
flocculating
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.)
Ceased
Application number
AU67035/90A
Other versions
AU6703590A (en
Inventor
Walter Luem
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SEETAL SPRAY BOOTH Pty Ltd
Original Assignee
SEETAL SPRAY BOOTH Pty Ltd
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 SEETAL SPRAY BOOTH Pty Ltd filed Critical SEETAL SPRAY BOOTH Pty Ltd
Priority to AU67035/90A priority Critical patent/AU629069B2/en
Publication of AU6703590A publication Critical patent/AU6703590A/en
Application granted granted Critical
Publication of AU629069B2 publication Critical patent/AU629069B2/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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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
    • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
    • B01D29/09—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with filtering bands, e.g. movable between filtering operations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
    • B01D29/11—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with bag, cage, hose, tube, sleeve or like filtering elements
    • B01D29/13—Supported filter elements
    • B01D29/23—Supported filter elements arranged for outward flow filtration
    • B01D29/27—Filter bags
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
    • B01D29/50—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with multiple filtering elements, characterised by their mutual disposition
    • B01D29/52—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with multiple filtering elements, characterised by their mutual disposition in parallel connection
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
    • B01D29/60—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor integrally combined with devices for controlling the filtration
    • B01D29/605—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor integrally combined with devices for controlling the filtration by level measuring
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
    • B01D29/88—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor having feed or discharge devices
    • B01D29/90—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor having feed or discharge devices for feeding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
    • B01D29/96—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor in which the filtering elements are moved between filtering operations; Particular measures for removing or replacing the filtering elements; Transport systems for filters
    • 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
    • B01D33/72—Filters with filtering elements which move during the filtering operation having feed or discharge devices for feeding
    • 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
    • B01D33/80—Accessories
    • B01D33/801—Driving means, shaft packing systems or the like
    • 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
    • B01D33/80—Accessories
    • B01D33/804—Accessories integrally combined with devices for controlling the filtration
    • B01D33/807—Accessories integrally combined with devices for controlling the filtration by level measuring
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D37/00—Processes of filtration
    • B01D37/03—Processes of filtration using flocculating agents
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D37/00—Processes of filtration
    • B01D37/04—Controlling the filtration
    • B01D37/045—Controlling the filtration by level measuring

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Filtration Of Liquid (AREA)

Description

r- SAUSTRALI A PATENTS ACT COMPLETE SPECIFICATION
SORIGINAL
(FOR OFFICE USE) SClass Int Class Application Number: i Lodged: i Complete Specification Lodged: Accepted: Pub ished: Priority: Related Art: Name of Applicant(s): .SEETAL SPRAY BOOTH PTY LTD Address of Appl icant(s): .56 Jersey Road, Bayswater, Victoria,3153 Actual Inventor(s) t '4 i Address for Service: PATENT ATTORNEY SERVICES 26 Ellingworth Parade, Box Hill, Victoria 3128 Complete specification for the invention entitled: WASTE WATER FILTRATION The following statement is a full description of this invention, including the best method of performing it known to s 1.
r ,i 'I This invention relates to waste water treatment.
Spray booths are used in automotive workshops, factories and in other industries requiring spray or powder coating of articles. Such booths can be provided with a water curtain which traps airborne particles before they escape to surrounding atmosphere. The spray booths are provided with water vessels below the spray curtains so that water spray including the collected airborne particles are collected in the vessels.
Periodically the vessels are emptied and the waste water which incorporates the trapped airborne particles is removed for G oo S treatment off site before it can be discharged.
o It is an object of the present invention to provide a o waste water filtration apparatus which can be used at a site where waste water is collected.
It is a preferred object of the present invention to S provide a waste water filtration apparatus which enables treated a waste water to be recycled for immediate reuse.
It is a further preferred object of the present invention *48084 to provide a waste water filtration apparatus which is oru relatively simple and effective in operation and which can be S compact for use at the site where the waste water is produced.
According to the present invention there is provided a waste water filtration apparatus for treating waste water, the apparatus including a flocculating stage including means for introduction of measured quantities of flocculating agent(s) to waste water to cause formation of flocs of material in the waste water, and filtration apparatus including support means for supporting a disposable porous filtration medium so as to L- receive and retain waste water and allow water to pass through the filtration medium, the waste water from the flocculating stage being supplied to the filtration apparatus after the formation of flocs, the filtration medium being selectively removable from the support means when the capacity thereof for receiving and filtering more waste water is effectively reduced by a predetermined degree, the support means being arranged to receive further or additional filtration medium to allow resumption of or continued waste water treatment.
o° 1o 0The flocculating stage may compiise a flocculating vessel S to which waste water is supplied, level sensing means for °o sensing the level of waste water within the flocculating vessel, and dosing means for dispensing a predetermined dose of 0 0O flocculating agent in response to the level sensing means sensing that the waste water within the vessel has reached a predetermined level.
f Preferably the flocculating stage includes agitating means for creating turbulant mixing of the flocculating agent with the So waste water so as to promote the formation of flocs.
In one possible embodiment the filtration medium comprises o a filter bag having an open top, the filter bag being releasably o 8 9* supported by the support means so that waste water having the flocs therein is supplied through the open top into the filter bag, the filter bag being porous so as to allow water to pass therethrough and being selectively removable from the support means for disposal of the bag and separated solids within the bag.
In this first embodiment, the filtration apparatus may include support means for supporting a plurality of the filter
I
;i I
I~
'I
o a a, bags, the filtration apparatus further including distribution means for distributing waste water from the flocculating stage to the plurality of filter bags. Also, the filtration apparatus includes a collection means arranged below the filtration medium so as to collect for recycling or disposal water passing through the filtration medium.
The flocculating vessel may comprise a collection vessel for collecting waste water flowing by gravity into the collection vessel from associated apparatus, the dosing means 3@ being arranged to supply flocculating agent to the collection a, Svessel at a dosing point, the collection vessel having an outlet aa remote from the dosing point and from which waste water is removed from the vessel and passed to the filtration apparatus.
In a second embodiment the filtration medium may comprise a filter sheet and the support means may comprise a shallow upwardly facing concave support having a lower discharge port through which clarified water from the filter sheet passes. The filter sheet may comprise a continuous sheet of porous filter material, the filtration apparatus including feed means for a feeding the filter sheet to the support so as to replace used filtration medium with unused filter sheet. The continuous filter sheet may be provided in a roll and the feed means may be operative to rotate the roll to progressively peel the filter sheet from the roll and feed it to the support means. The continuous filter sheet after use may be fed from the support means to an open topped container for disposal of the filter sheet and the solids that have been separated from the waste water by the filter sheet.
It
II
LI
I a I I i i I In this second embodiment, the filtration apparatus may include sensing means for sensing the level of waste water and separated solids material above the support means so as to control the feeding of waste water to the support means and to control the supply of the filter sheet.
Possible and preferred features of the present invention will now be described with particular reference to the accompanying drawings. However it is to be understood that the features illustrated in and described with reference to the drawings are not to be construed as limiting on the scope of the 0, S invention. In the drawings: oto 00 0 0 00i 04 04* 01 Fig. 1 shows schematically a side elevational view of a first apparatus according to the present invention, and Fig. 2 shows schematically a side elevational view of a second possible embodiment of apparatus according to the present invention.
Referring to Fig. 1, there is shown an apparatus 10 which may for example comprise a spray booth where vehicles, 0 Smanufactured components, or the like can be sprayed with paint or powder. The apparatus 10 may include a water spray curtain (not shown) which traps airborne particles and these particles in the water are collected in the collection vessel 12.
Waste water 11 from the collection vessel 12 is fed by pump 13 through transfer line 14 to the flocculating stage The flocculating stage 15 includes a vessel 16 which receives the waste water from the transfer line 14. Level sensing means 17 is responsive to the level of water of within the vessel 16 and when the water reaches a predetermined level the sensing means 17 initiates operation of the dosing means Sr7. The dosing means 20 comprises a storage vessel 21 for flocculating agent and a metering device 22 associated with the outlet of the storage vessel 21 so that when the level of waste water in the vessel 16 'eaches the predetermined level, a predetermined dose of flocculating agent is dispensed from the storage vessel 21.
Within the vessel 16 is agitating means 25 shown as an agitating paddle driven by motor 26, the agitating means creating turbulence within the vessel 16 so as to promote thorough mixing of the flocculating agent and thereby the S formation of flocs.
too *oqo ,After the forrmation of flocs in the vessel 16, the waste .o water is transferred by means of pump 30 through line 31 to distribution means 32 shown as a distribution tank or manifold.
Waste water which includes the flocs is then passed to the filter bags 33. The filter bags are provided with open tops I4r a which are removably mounted to support chutes so that the bags are suspended from the distribution means 32. The filter bags a 33 are made of a porous material such as woven polypropylene.
a 20 The bags 33 retain the flocs and sludge and the water seeps through to the outside of the bags. When the bags are substantially full, they can be removed for disposal. For example, the bags may be slit open and the contents dried so as to form a solid waste for disposal.
The water that is passed through the bags 33 is collected in collection tray or the like 34 and returned to vessel The water in vessel 45 can be returned by pump 36 to' the spray booth tank 12 for reuse or can be discharged to the sewerage system. The pH of the discharged or recirculated water can be adjusted if necessary.
I 4 t 1 i, i In Fig. 2 the apparatus 10 is again shown as a spray booth in which water curtains are generated to trap airborne particles. The water for the curtains is drawn from the tank t 4 440 oo 04 40 4 4 V j 1.4 The tank 12 in Fig. 2 serves as the flocculating stage.
Flocculating agent is supplied from storage vessel 21 by dispensing means 22 shown as an auger. Remote from the point where the flocculating agent is introduced into the tank 12 there is provided a pump 13 which pumps waste water including 'f flocs through transfer line 14 to the filtration apparatus a *0 o The filtration apparatus includes a support means shown in 00 the form of a porous belt 18 which passes around rollers 19 so g" as to form a shallow concave support for continuous sheet filter 1t Smedium 41 fed from roll 40. The supply of waste water to the support and to the sheet filter medium 41 is controlled by level sensor 42 which controls feed means (not shown) operative to rotate the roll 40 to peel off more filter medium. The sheet filter 41 can be continuously or intermittently advanced and the It used sheet filter material is fed to a container 45 such as a 20 bin from which the used filter medium 41 and the sludge and flocs and other solid matter trapped thereby can be subsequently removed for disposal. Water passing through the filter medium 41 and the porous support belt 18 is collected by collection cone 46. As shown, the collected waste water zan be returned through line 47 to the tank 12 for reuse or can be passed through line 48 to sewerage system It will be seen that the apparatus described and illustrated in both Figs. 1 and 2 can be relatively simple and effective in operation. The waste water can be recycled or 44' t t04 4% c discharged to the sewerage system and the separated solids which are adhereing to the filter material can be disposed of as a solid waste. It will also be seen that the apparatus described and illustrated can be relatively simple in construction operation and maintenance and can therefore be affordable for moderate sized businesses.
It is to be understood that various alterations, modifications and/or additions may be made to the features of the possible and preferred embodiment(s) of the invention as herein described without departing from the spirit and scope of the invention as defined in the appended claims.
te 00 4It t 0 0 4 t

Claims (6)

  1. 2. Apparatus as claimed in Claim 1 wherein the flocculating Sstage comprises a flocculating vessel to which waste water is 28 supplied, level sensing means for sensing the level of waste water within the flocculating vessel, and dosing means for dispensing a predetermined dose of flocculating agent in response to the level sensing means sensing that the waste water within the vessel has reached a predetermined level.
  2. 3. Apparatus as claimed in Claim 1 or 2 wherein the flocculating stage includes agitating means for creating turbulant mixing of the flocculating agent with the waste water so as to promote the formation of flocs. I i i .0- 0's 99 0 0 0 0 90,
  3. 9.0 4. Apparatus as claimed in any one of the preceding claims wherein the filtration medium comprises a filter bag having an open top, the filter bag being releasably supported by the support means so that waste water having the flocs therein is supplied through the open top into the filter bag, the filter bag being porous so as to allow water to pass therethrough and being selectively removable from the support means for disposal of the bag and separated solids within the bag. Apparatus as claimed in Claim 4 wherein the filtration 7f- apparatus includes support means for supporting a plurality of 09 Sthe filter bags, the filtration apparatus further including o distribution means for distributing waste water from the 'Po flocculating stage to the plurality of filter bags. 00 6. Apparatus as claimed in Claim 4 or 5 wherein the filtration apparatus includes a collection means arranged below the filtration medium so as to collect for recycling or disposal ,o water passing through the filtration medium. 7. Apparatus as claimed in Claim 2 wherein the flocculating vessel comprises a collection vessel for collecting waste water 20 flowing by gravity into the collection vessel from associated oo apparatus, the dosing means being arranged to supply flocculating agent to the collection vessel at a dosing point, the collection vessel having an outlet remote from the dosing point and from which waste water is removed from the vessel and passed to the filtration apparatus. 8. Apparatus as claimed in any one of Claims 1 to 3 wheren the filtration medium comprises a filter sheet and the support means comprises a shallow upwardly facing concave support having a lower discharge port through which clarified water from the 00 0. 0o 0~ filter sheet passes. 9. Apparatus as claimed in Claim 8 wherein the filter sheet comprises a continuous sheet of porous filter material, the filtration apparatus including feed means for feeding the filter sheet to the support so as to replace used filtration medium with unused filter sheet. Apparatus as claimed in Claim 9 wherein the continuous filter sheet is provided in a roll and the feed means is operative to rotate the roll to progressively peel the filter sheet from the roll and feed it to the support means.
  4. 11. Apparatus as claimed in Claim 9 or 10 wherein the continuous filter sheet after use is fed from the support means to an open topped container for disposal of the filter sheet and 4a "g the solids that have been separated from the waste water by the filter sheet.
  5. 12. Apparatus as claimed in any one of Claims 8 to 11 wherein the filtration apparatus includes sensing means for sensing the level of waste water and separated solids material above the support means so as to control the feeding of waste water to the support means and to control the supply of the filter sheet. 4
  6. 13. Waste water filtration apparatus substantially as herein before described with particular reference to the accompanying drawings. Dated this 19th day of November, 1990 PATENT ATTORNEY SERVICES Attorneys for SEETAL SPRAY BOOTH PTY LTD
AU67035/90A 1990-11-27 1990-11-27 Waste water filtration Ceased AU629069B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU67035/90A AU629069B2 (en) 1990-11-27 1990-11-27 Waste water filtration

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
AU67035/90A AU629069B2 (en) 1990-11-27 1990-11-27 Waste water filtration

Publications (2)

Publication Number Publication Date
AU6703590A AU6703590A (en) 1992-05-28
AU629069B2 true AU629069B2 (en) 1992-09-24

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Family Applications (1)

Application Number Title Priority Date Filing Date
AU67035/90A Ceased AU629069B2 (en) 1990-11-27 1990-11-27 Waste water filtration

Country Status (1)

Country Link
AU (1) AU629069B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0659689A2 (en) * 1993-12-03 1995-06-28 AWL AG für Wasser- und Lufttechnik Eliminating dispersions

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DK168703B1 (en) * 1992-06-18 1994-05-24 Nordfab As Process and plant for cleaning liquid containing sludge from grinding processes

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU1658688A (en) * 1987-05-26 1988-12-01 Calgon Corporation Process for detackification of paint spray operation wastes using melamine formaldehyde
AU2214288A (en) * 1987-09-18 1989-03-23 PPK Environment & Infrastructure Pty Limited Improved method and apparatus for clarifying water

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU1658688A (en) * 1987-05-26 1988-12-01 Calgon Corporation Process for detackification of paint spray operation wastes using melamine formaldehyde
AU2214288A (en) * 1987-09-18 1989-03-23 PPK Environment & Infrastructure Pty Limited Improved method and apparatus for clarifying water

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0659689A2 (en) * 1993-12-03 1995-06-28 AWL AG für Wasser- und Lufttechnik Eliminating dispersions
EP0659689A3 (en) * 1993-12-03 1995-10-25 Wasser & Lufttech Eliminating dispersions.

Also Published As

Publication number Publication date
AU6703590A (en) 1992-05-28

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MK14 Patent ceased section 143(a) (annual fees not paid) or expired