WO1998018730A1 - Sludge dewatering control system - Google Patents
Sludge dewatering control system Download PDFInfo
- Publication number
- WO1998018730A1 WO1998018730A1 PCT/AU1997/000723 AU9700723W WO9818730A1 WO 1998018730 A1 WO1998018730 A1 WO 1998018730A1 AU 9700723 W AU9700723 W AU 9700723W WO 9818730 A1 WO9818730 A1 WO 9818730A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- sludge
- dewatering
- additive
- particle structure
- control
- Prior art date
Links
- 239000010802 sludge Substances 0.000 title claims abstract description 210
- 238000000034 method Methods 0.000 claims abstract description 94
- 239000000654 additive Substances 0.000 claims abstract description 61
- 230000000996 additive effect Effects 0.000 claims abstract description 59
- 239000002245 particle Substances 0.000 claims abstract description 45
- 239000007787 solid Substances 0.000 claims abstract description 38
- 238000012544 monitoring process Methods 0.000 claims abstract description 10
- 229920000642 polymer Polymers 0.000 claims description 35
- 238000001374 small-angle light scattering Methods 0.000 claims description 22
- 238000012545 processing Methods 0.000 claims description 19
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 16
- 238000005259 measurement Methods 0.000 claims description 8
- 238000012512 characterization method Methods 0.000 claims description 6
- 230000007246 mechanism Effects 0.000 claims description 6
- 230000000694 effects Effects 0.000 claims description 5
- 239000010801 sewage sludge Substances 0.000 claims description 5
- 230000001105 regulatory effect Effects 0.000 claims description 3
- 230000008569 process Effects 0.000 description 20
- 238000010586 diagram Methods 0.000 description 7
- 239000012895 dilution Substances 0.000 description 7
- 238000010790 dilution Methods 0.000 description 7
- 238000004458 analytical method Methods 0.000 description 4
- 238000004065 wastewater treatment Methods 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 3
- 230000001276 controlling effect Effects 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000011368 organic material Substances 0.000 description 3
- 238000005070 sampling Methods 0.000 description 3
- 239000002699 waste material Substances 0.000 description 3
- 241000894006 Bacteria Species 0.000 description 2
- 230000001143 conditioned effect Effects 0.000 description 2
- 229910010272 inorganic material Inorganic materials 0.000 description 2
- 239000011147 inorganic material Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 238000002834 transmittance Methods 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000011088 calibration curve Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000000701 coagulant Substances 0.000 description 1
- 230000015271 coagulation Effects 0.000 description 1
- 238000005345 coagulation Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000008394 flocculating agent Substances 0.000 description 1
- 230000003760 hair shine Effects 0.000 description 1
- CPBQJMYROZQQJC-UHFFFAOYSA-N helium neon Chemical compound [He].[Ne] CPBQJMYROZQQJC-UHFFFAOYSA-N 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- JRSGPUNYCADJCW-UHFFFAOYSA-K iron(3+);trichlorate Chemical compound [Fe+3].[O-]Cl(=O)=O.[O-]Cl(=O)=O.[O-]Cl(=O)=O JRSGPUNYCADJCW-UHFFFAOYSA-K 0.000 description 1
- 210000003127 knee Anatomy 0.000 description 1
- 238000002356 laser light scattering Methods 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 229920000867 polyelectrolyte Polymers 0.000 description 1
- 239000012898 sample dilution Substances 0.000 description 1
- 239000010865 sewage Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/12—Treatment of sludge; Devices therefor by de-watering, drying or thickening
- C02F11/14—Treatment of sludge; Devices therefor by de-watering, drying or thickening with addition of chemical agents
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/02—Investigating particle size or size distribution
- G01N15/0205—Investigating particle size or size distribution by optical means
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/12—Treatment of sludge; Devices therefor by de-watering, drying or thickening
- C02F11/14—Treatment of sludge; Devices therefor by de-watering, drying or thickening with addition of chemical agents
- C02F11/147—Treatment of sludge; Devices therefor by de-watering, drying or thickening with addition of chemical agents using organic substances
Definitions
- sludge refers to substantially settled solid coagulated material derived from a treatment process.
- the sludge has added to it an additive for the purpose of improving the dewaterability behaviour of the sludge when processed through a dewatering device such as a centrifuge, belt press, filter press or the like.
- the dewatering device produces two outputs, namely dewatered sludge which is termed “cake” and the residual watery sludge driven from the cake which is termed a “watery stream” .
- the dewatering device is a centrifuge or cyclone the watery stream is also termed a "centrate”.
- the term “continuously monitoring the structure of the sludge” refers to a process of monitoring which is automatic and periodic in obtaining samples for processing.
- the method of control and the control system implementation of the method are “continuous” in the sense that whilst the taking of samples is a necessarily sequential process the total process of obtaining samples, analysing them and acting on the analysis will be continuous. Also the sampling will be performed at a sufficient rate to match with the control time constant required of the process.
- a method of control of dewatering of sludge comprising obtaining a relationship between particle structure and cake solids content of said sludge, continuously monitoring said particle structure of said sludge so as to provide a continuous determination of said cake solids content of said sludge and adding an additive to said sludge as a function of said cake solids content so as to control the dewatering characteristics of said sludge.
- said additive is a polymer.
- said sludge is sewage sludge.
- said sludge is a sludge and additive mix.
- said monitor utilises small angle light scattering (SALS ) equipment to determine said mass fractal dimension in conjunction with data processing means so as to effect control of the dewatering characteristics of said sludge.
- SALS small angle light scattering
- control is effected by reference to a predetermined relationship of additive dose against mass fractor dimension of said sludge.
- control is effected by reference to a predetermined relationship of cake solids content against fractor dimension of said sludge.
- particle structure is determined by obtaining a sample of said sludge after addition of said additive and before dewatering.
- a method of control of dewatering of sludge comprising obtaining a relationship between particle structure of said sludge and dewaterability of said sludge, monitoring said particle structure of said sludge so as to provide a determination of said dewaterability of said sludge and regulating the addition of an additive to said sludge in accordance with said relationship thereby to control the dewatering of said sludge.
- Fig 1. is a process diagram of a sludge dewatering control system according to a first embodiment of the invention and, Fig 2. is a graph of the relationship between sludge particle structure and cake solids content suitable for providing relationship data as an input to the control system of Fig 1, Fig 3. is a process diagram of a sludge dewatering control system according to a second embodiment of the invention, Fig 4. is a graph illustrating cake solids concentration against feed fractal dimension and centrate solids content against feed fractal dimension in relation to the system of Fig 3,
- Fig 5. is process diagram of a sludge dewatering control system according to a third embodiment of the invention
- Fig 6. is a graph of cake solids content against centrate fractal dimension and centrate solids content against centrate fractal dimension in relation to the system of Fig
- Fig 7. is a process diagram of a sludge dewatering control system implementing the system of Fig 5,
- Fig. 8 is a graph of the relationship between intensity of scattered light and momentum transfer from which fractal dimension can be calculated for the system of Fig 7,
- Fig 9 is a diagram of a combined dilution and small angle light scattering cell for use with the system of Fig 7 and
- Fig 10 is a flow diagram of a software implementation for use with the system of Fig 7, and
- Fig 11A is a graph of cake solids content against polymer content of an exemplary sludge and,
- Fig 11B is a graph of fractal dimension against polymer content for an exemplary sludge with polymer combination.
- Embodiments of the invention to be described rely on the combination of two key observations.
- cake solids content dewaterablility
- proportion of additive polymer
- fractal dimension can be used as a control variable to maximise cake solids content (dewaterability) around an optimal concentration of additive - in this instance polymer.
- FIG 1. A first preferred embodiment of the invention is illustrated in Fig 1. which comprises a flowchart of a control process for application to a sludge dewatering system.
- the dewatering system 10 includes a waste water treatment tank 11 wherein bacteria are present or a flocculant (not shown) is added to the waste water under treatment and which results in the formation of a sludge 12 which settles to the bottom of the tank 11 and which is removed via sludge outlet 13 for supply to a dewatering unit 14 via dewatering inlet 15.
- the dewatering unit can comprise a belt unit or a centrifuge unit or other known mechanism for the removal of water from sludge.
- the dewatered waste 16 is discharged from dewatering unit 14 via exit pipe 17 for transport by truck or similar to another site.
- the dewatering system 10 further includes a dosing device 18 which is adapted to add predetermined amounts of an additive 19 to the sludge 12 prior to dewatering by dewatering unit 14.
- the additive is a polymer of the type known to provide assistance in the improvement of dewatering characteristics of sludge 12.
- a control system 20 is applied to the dosing device 18 whereby the amount and timing of polymer dose administered by dosing device 18 is controlled by microprocessor or data processing device 21 in reliance upon input data 22 and relationship data 23.
- the relationship data 23 provides a mathematical relationship between solids content of sludge 12 and its structure, more particularly its structure as relevant to determining the dewatering characteristics of the sludge.
- the input data 22 is derived from a monitor which contiguously monitors the structure of the sludge 12 prior to processing by dewatering unit 14.
- the monitor is a small angle light scattering (SALS) unit 24 so as to provide a substantially continuous indication of the structure of the sludge 12 to data processing device 21.
- the data processing device 21 utilises this input data 22 in conjunction with the structure/solids content relationship derived via relationship monitor 25 to determine an estimate of the solids content of sludge 12 and thence to apply a control signal 26 to dosing device 18 so as to adjust the dose of polymer of like additive administered by dosing device 18 with the end result of controlling the dewaterability of the sludge entering dewatering unit 14.
- SALS small angle light scattering
- the dewatering unit can comprise a belt filter, or vacuum filter, or a centrifuge unit or other known mechanism for the removal of water from the sludge.
- the dewatered sludge cake 108 is discharged from the dewatering unit for further treatment or disposal as well as the watery stream 109 which is usually recycled.
- the relationship data 113 provides a relationship between sludge structure as relevant to determining the dewatering characteristics of the sludge.
- a sample 110 is taken of the mixed sludge and polymer stream 106 for analysis by the structure monitor.
- Figure 5 is a process diagram of a sludge dewatering control system according to a third embodiment of the invention and Figure 6 is a graph of the relationship between structure of the solids leaving the dewatering unit in the watery stream.
- the dewatering system includes a treatment tank 201 which results in the formation of a sludge 202 which is removed for supply to a dewatering unit 207.
- the dewatering unit can comprise a belt filter, or vacuum filter, or a centrifuge unit or other known mechanism for the removal of water from the sludge.
- the dewatered sludge cake 208 is discharged from the dewatering unit for further treatment or disposal as well as the watery stream 209 which is usually recycled.
- the dewatering system further includes a dosing device
- the additive is a polymer of the type know to provide assistance in the improvement of dewatering characteristics of sludge 202.
- the relationship data 213 provides a relationship between sludge structure as relevant to determining the dewatering characteristics of the sludge.
- the flow chart requires a comparison of the fractal dimension measurement obtained (dF) with the "inbuilt" dF v polymer dose relationship obtained from previous calibration tests.
- this relationship can also be a relationship of cake solids content versus fractal dimension of the sample as per Figs 2, 4 and 6 (permissible as the result of superposition of Figs 11A and 11B as described earlier in the specification).
- the embodiments of the invention can be applied to processes which dewater sludge so as to optimise additive addition. Such processes are found in water and waste water treatment plants, mineral processing plants and the like.
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Dispersion Chemistry (AREA)
- Physics & Mathematics (AREA)
- General Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Treatment Of Sludge (AREA)
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP97909064A EP0946435A4 (de) | 1996-10-29 | 1997-10-29 | Kontrolsystem zur schlammentwässerung |
| AU46937/97A AU4693797A (en) | 1996-10-29 | 1997-10-29 | Sludge dewatering control system |
| JP10519818A JP2001502601A (ja) | 1996-10-29 | 1997-10-29 | スラッジ除水制御システム |
| CA002270207A CA2270207A1 (en) | 1996-10-29 | 1997-10-29 | Sludge dewatering control system |
| NO992070A NO992070L (no) | 1996-10-29 | 1999-04-29 | Kontrollsystem for slamavvanning |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AUPO3285 | 1996-10-29 | ||
| AUPO3285A AUPO328596A0 (en) | 1996-10-29 | 1996-10-29 | Sludge dewatering control system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO1998018730A1 true WO1998018730A1 (en) | 1998-05-07 |
Family
ID=3797594
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/AU1997/000723 WO1998018730A1 (en) | 1996-10-29 | 1997-10-29 | Sludge dewatering control system |
Country Status (7)
| Country | Link |
|---|---|
| EP (1) | EP0946435A4 (de) |
| JP (1) | JP2001502601A (de) |
| KR (1) | KR20000052923A (de) |
| AU (1) | AUPO328596A0 (de) |
| CA (1) | CA2270207A1 (de) |
| NO (1) | NO992070L (de) |
| WO (1) | WO1998018730A1 (de) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002076890A2 (de) * | 2001-03-27 | 2002-10-03 | Clausthaler Umwelttechnikinstitut Gmbh (Cutec-Institut) | Verfahren und messanordnung zur automatischen bestimmung des aufkonzentrierungsfaktors von konditioniertem klärschlamm |
| WO2020013698A1 (en) | 2018-07-13 | 2020-01-16 | Haskoningdhv Nederland B.V. | Method for dewatering watery biomass |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108693775A (zh) * | 2018-05-24 | 2018-10-23 | 株洲时代新材料科技股份有限公司 | 一种全自动、自适应、比例调控的污泥调理方法 |
| CN112777918B (zh) * | 2020-12-11 | 2022-08-12 | 北京林业大学 | 一种基于分形维数和粒度的污泥氧化调理在线控制方法 |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0316997A2 (de) * | 1987-11-19 | 1989-05-24 | Calgon Corporation | System und Verfahren zum Überwachen und Regeln eines Flüssig-Fest-Trennungsverfahrens |
| AU3874193A (en) * | 1992-06-09 | 1993-12-16 | Anikem (Pty) Limited | Dewatering of slurries |
| US5534139A (en) * | 1993-11-12 | 1996-07-09 | Andritz-Patentverwaltungs-Gesellschaft M.B.H. | Apparatus for controlling solids-liquid separation |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3412620A1 (de) * | 1984-04-04 | 1985-10-17 | Basf Ag, 6700 Ludwigshafen | Laseroptische anordnung zur messung des dispergiergrades in stroemenden systemen |
| CA1326079C (en) * | 1986-12-22 | 1994-01-11 | Walti Schmitt | Process for conditioning and dewatering sludges |
| DE4029825A1 (de) * | 1990-09-20 | 1992-03-26 | Passavant Werke | Verfahren und vorrichtung zum konditionieren und anschliessenden entwaessern von schlaemmen |
| DE4442418A1 (de) * | 1994-11-29 | 1996-05-30 | Joachim Friedrich Knauer | Vorrichtung zur Steuerung der Flockungsmittelzugabe zu einem wäßrigen Schlamm |
-
1996
- 1996-10-29 AU AUPO3285A patent/AUPO328596A0/en not_active Abandoned
-
1997
- 1997-10-29 JP JP10519818A patent/JP2001502601A/ja active Pending
- 1997-10-29 CA CA002270207A patent/CA2270207A1/en not_active Abandoned
- 1997-10-29 WO PCT/AU1997/000723 patent/WO1998018730A1/en not_active Application Discontinuation
- 1997-10-29 EP EP97909064A patent/EP0946435A4/de not_active Withdrawn
- 1997-10-29 KR KR1019990703791A patent/KR20000052923A/ko not_active Application Discontinuation
-
1999
- 1999-04-29 NO NO992070A patent/NO992070L/no not_active Application Discontinuation
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0316997A2 (de) * | 1987-11-19 | 1989-05-24 | Calgon Corporation | System und Verfahren zum Überwachen und Regeln eines Flüssig-Fest-Trennungsverfahrens |
| AU3874193A (en) * | 1992-06-09 | 1993-12-16 | Anikem (Pty) Limited | Dewatering of slurries |
| US5534139A (en) * | 1993-11-12 | 1996-07-09 | Andritz-Patentverwaltungs-Gesellschaft M.B.H. | Apparatus for controlling solids-liquid separation |
| US5626766A (en) * | 1993-11-12 | 1997-05-06 | Andritz-Patentverwaltungs-Gesellschaft M.B.H. | Process for controlling solids-liquid separation |
Non-Patent Citations (1)
| Title |
|---|
| See also references of EP0946435A4 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002076890A2 (de) * | 2001-03-27 | 2002-10-03 | Clausthaler Umwelttechnikinstitut Gmbh (Cutec-Institut) | Verfahren und messanordnung zur automatischen bestimmung des aufkonzentrierungsfaktors von konditioniertem klärschlamm |
| WO2002076890A3 (de) * | 2001-03-27 | 2003-01-03 | Clausthaler Umwelttechnikinsti | Verfahren und messanordnung zur automatischen bestimmung des aufkonzentrierungsfaktors von konditioniertem klärschlamm |
| WO2020013698A1 (en) | 2018-07-13 | 2020-01-16 | Haskoningdhv Nederland B.V. | Method for dewatering watery biomass |
| NL2021302B1 (en) * | 2018-07-13 | 2020-01-20 | Haskoningdhv Nederland Bv | Method for dewatering watery biomass |
Also Published As
| Publication number | Publication date |
|---|---|
| CA2270207A1 (en) | 1998-05-07 |
| JP2001502601A (ja) | 2001-02-27 |
| EP0946435A1 (de) | 1999-10-06 |
| KR20000052923A (ko) | 2000-08-25 |
| EP0946435A4 (de) | 2000-01-26 |
| NO992070D0 (no) | 1999-04-29 |
| NO992070L (no) | 1999-06-11 |
| AUPO328596A0 (en) | 1996-11-21 |
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