CN109368984A - A kind of method of continuous Floatation Thickening Sludge - Google Patents
A kind of method of continuous Floatation Thickening Sludge Download PDFInfo
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- CN109368984A CN109368984A CN201811552068.5A CN201811552068A CN109368984A CN 109368984 A CN109368984 A CN 109368984A CN 201811552068 A CN201811552068 A CN 201811552068A CN 109368984 A CN109368984 A CN 109368984A
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- 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
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- 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
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- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
- Treatment Of Sludge (AREA)
Abstract
A kind of method of continuous Floatation Thickening Sludge, it is characterized in that, the following steps are included: the sludge after pre-concentration is pumped into reactor tank, glass transition temperature is continuously added in proportion into reactor tank higher than the pH of room temperature and amine (ammonium) solution of temperature-responsive polyacrylate analog copolymer, is uniformly mixed；It is continuously added to acid, conversion zone is entered after mixing and reacts 5-20min, sludge pH is 4-6 after reaction；Sludge is pumped into preheating can, gravity flow enters heating tank and heated after preheating by heat exchange, and keeps the temperature 5-20min；Dirty overflow enters air floatation machine progress floatation thickening in heating tank；Thickened sludge is cooled below temperature-responsive polyacrylate copolymer Tg hereinafter, between the mud granule for forming copolymer hardening rear support then hole, reduction sludge specific resistance remove filtering means dehydration.
Description
Technical field
The invention belongs to the sewage in environmental protection, technical field of sludge treatment, in particular to a kind of continuous floatation thickening
The method of sludge.
Background technique
A large amount of sludge can be generated in sewage disposal process, volume is big, and moisture content is high, typically up to 98-99%, therefore
The dehydration of sludge is always global problem.It is mechanical when being carried out using plate and frame filter press, belt type dewaterer or centrifugal dehydrator etc.
Rate of water loss is slow when the solid-liquid separating methods such as dehydration or vacuum dehydration are dehydrated, and dewatering time is long.
The minimizing of sludge volume is one of vital task of Treatment of Sludge, therefore usually requires first to carry out before sludge dewatering
Concentration to reduce sludge volume, but usually contains a large amount of hydrophilic organics hydrophilicity in sludge, hydrophily is strong, viscosity
Greatly, it in conjunction with water content height, is difficult to reach good concentration effect using conventional sludge condensation technology such as precipitation concentration, floatation thickening
Fruit.The problems such as it is low that there are cycles of concentration, and reduction is poor, sludge volume is still huge after concentration, and some sludge is even difficult
With floatation thickening, sludge dewatering is difficult.
Summary of the invention
The purpose of the present invention is to provide a kind of methods of continuous Floatation Thickening Sludge, improve sludge volume minimizing journey
Degree is concentrated sludge high power, and reduces the resistivity of thickened sludge, improves sludge dewatering speed.
To realize above-mentioned goal of the invention, the technical method that the present invention uses are as follows:
A kind of method of continuous Floatation Thickening Sludge, which is characterized in that pH and temperature-responsive polyacrylic acid are added into sludge
Ester copolymer is precipitated its reaction, changes its physical state by temperature change to the response of temperature with copolymer molecule chain, real
The concentration of existing sludge, and reduce sludge specific resistance, comprising the following steps:
(1) sludge after pre-concentration is pumped into reactor tank, continuously adds vitrifying in proportion into reactor tank level-one mixing section
Temperature (Tg) is higher than the pH of room temperature and amine (ammonium) solution of temperature-responsive polyacrylate analog copolymer, dosage 2-10g/
L sludge, is uniformly mixed；
(2) it is continuously added to acid into reactor tank second level mixing section while stirring, enters conversion zone later and react 5-20min, makes to gather
The water soluble group of acrylate copolymer sloughs amine (ammonium) base by ion exchange, and formation-COOH reduces copolymer
Solubility, make copolymer molecule be sufficiently precipitated and with mud granule by van der Waals interaction absorption combined, sludge after reaction
PH is 4-6；
(3) sludge is pumped into preheating can by sludge pump after reacting, and gravity flow enters heating tank and heated after being preheated by heat exchange, makes
Temperature is increased to Tg or more the 5-20 DEG C of polyacrylate copolymer, changes its physical state, rolls up copolymer molecule chain movement
Song keeps the temperature 5-20min, so that the copolymer molecule chain movement adsorbed with mud granule curling is driven mud granule one using heat effect
It rises and reunites, contraction distortion improves mud granule by hydrophobic groupings such as methyl, ethyl, ester groups in polyacrylate copolymer
Hydrophobicity, improve concentrated effect；
(4) dirty overflow enters air floatation machine progress floatation thickening in heating tank, and by thickened sludge is discharged at the top of air floatation machine, after air bearing
The water being concentrated out, for the sludge after pre- thermal response, is recycled thermal energy, then arranged by reflux sewage pump continuous backflow to heat exchange tank
Enter waste water treatment system；
(5) concentration paste sludge is cooled below temperature-responsive polyacrylate copolymer Tg hereinafter, keeping copolymer extensive
It is multiple to harden hole between the mud granule that rear support is formed at glassy state, sludge specific resistance is reduced, filtering means dehydration is then removed.
The utility model has the advantages that
A. sludge volume can be reduced to 30% hereinafter, cycles of concentration improves 4 times or more than conventional precipitation concentration method, than conventional air bearing
Concentration method improves 2 times or more.
B. it is higher than the pH and temperature-responsive polyacrylate of room temperature with the glass transition temperature (Tg) that acid out in water phase is formed
The transformation that physical state occurs above and below glass transition temperature by the response to temperature for copolymer realizes that sludge-guarantor is cohered in softening
Warm drilling-hardening support is dehydrated pore canal role, goes out condensed water by gravity concentration, keeps the sludge for being difficult to be concentrated further dense
Contracting, reduction are obvious.
C. the effect of rolling up of polyacrylate copolymer Chain Flexibility segment, can drive mud granule height group after being heated
Poly- and deformation retract, makes sludge condensation and forms hole between mud granule, constitutes dehydration duct when filtering means dehydration
D. the carboxyl in pH and temperature-responsive copolymer being precipitated can be acted on the hydrophilic group of mud granule, reduce mud granule
Active force between water, while the hydrophobic groupings such as methyl, ethyl, ester group in copolymer on soft segment further increase dirt
The hydrophobicity of mud particle, and by the surface property of gas-liquid-solid three-phase interface change sludge, it reduces and combines water in thickened sludge
Content is conducive to sludge condensation.
E.pH and temperature-responsive polyacrylate copolymer are converted to hole between glassy state after-hardening support mud granule,
Sludge pore deformation, collapsing when can reduce filtering means dehydration, sludge specific resistance can be reduced to original 10% hereinafter, by sad after concentration
Filter sludge is transformed into easy filter sludge, and filtering velocity is accelerated, and shortens filtration time.
Detailed description of the invention
Fig. 1 is the artwork of continuous Floatation Thickening Sludge.
Specific embodiment
The present invention is further illustrated by specific embodiment with reference to the accompanying drawings of the specification.
Embodiment 1
(1) sludge after pre-concentration is pumped into reactor tank, continuously adds vitrifying in proportion into reactor tank level-one mixing section
Temperature (Tg) is higher than the pH of room temperature and amine (ammonium) solution of temperature-responsive polyacrylate analog copolymer, dosage 10g/L
Sludge is uniformly mixed；
(2) it is continuously added to acid into reactor tank second level mixing section while stirring, enters conversion zone later and react 15min, makes poly- third
The water soluble group of olefin(e) acid ester copolymer sloughs amine (ammonium) base by ion exchange, and formation-COOH reduces copolymer
Solubility makes copolymer molecule sufficiently be precipitated and be combined with mud granule by van der Waals interaction absorption, sludge pH after reaction
It is 4.8；
(3) sludge is pumped into preheating can by sludge pump after reacting, and gravity flow enters heating tank and heated after being preheated by heat exchange, makes
Temperature is increased to 20 DEG C of Tg or more of polyacrylate copolymer, crimps copolymer molecule chain movement, keeps the temperature 5min, utilizes heat
Effect makes reunites together with the copolymer molecule chain movement curling drive mud granule that mud granule adsorbs, and contraction distortion passes through
The hydrophobic groupings such as methyl, ethyl, ester group in polyacrylate copolymer improve the hydrophobicity of mud granule, improve concentration effect
Fruit；
(4) dirty overflow enters air floatation machine progress floatation thickening in heating tank, and by thickened sludge is discharged at the top of air floatation machine, after air bearing
The water being concentrated out, for the sludge after pre- thermal response, is recycled thermal energy, then drained by reflux water pump continuous backflow to heat exchange tank
Waste water treatment system；
(5) thickened sludge is cooled below temperature-responsive polyacrylate copolymer Tg hereinafter, being transformed into copolymer
Glassy state hardens hole between the mud granule that rear support is formed, and reduces sludge specific resistance, then removes filtering means dehydration.
Embodiment 2
(1) sludge after pre-concentration is pumped into reactor tank, continuously adds vitrifying in proportion into reactor tank level-one mixing section
Temperature (Tg) is higher than the pH of room temperature and amine (ammonium) solution of temperature-responsive polyacrylate analog copolymer, and dosage is 7g/L dirty
Mud is uniformly mixed；
(2) it is continuously added to acid into reactor tank second level mixing section while stirring, enters conversion zone later and react 10min, makes poly- third
The water soluble group of olefin(e) acid ester copolymer sloughs amine (ammonium) base by ion exchange, and formation-COOH reduces copolymer
Solubility makes copolymer molecule sufficiently be precipitated and be combined with mud granule by van der Waals interaction absorption, sludge pH after reaction
It is 4.5；
(3) sludge is pumped into preheating can by sludge pump after reacting, and gravity flow enters heating tank and heated after being preheated by heat exchange, makes
Temperature is increased to 5 DEG C of Tg or more of polyacrylate copolymer, crimps copolymer molecule chain movement, keeps the temperature 10min, utilizes heat
Effect makes reunites together with the copolymer molecule chain movement curling drive mud granule that mud granule adsorbs, and contraction distortion passes through
The hydrophobic groupings such as methyl, ethyl, ester group in polyacrylate copolymer improve the hydrophobicity of mud granule, improve concentration effect
Fruit；
(4) dirty overflow enters air floatation machine progress floatation thickening in heating tank, and by thickened sludge is discharged at the top of air floatation machine, after air bearing
The water being concentrated out, for the sludge after pre- thermal response, is recycled thermal energy, then drained by reflux water pump continuous backflow to heat exchange tank
Waste water treatment system；
(5) thickened sludge is cooled below temperature-responsive polyacrylate copolymer Tg hereinafter, being transformed into copolymer
Glassy state hardens hole between the mud granule that rear support is formed, and reduces sludge specific resistance, then removes filtering means dehydration.
Embodiment 3
(1) sludge after pre-concentration is pumped into reactor tank, continuously adds vitrifying in proportion into reactor tank level-one mixing section
Temperature (Tg) is higher than the pH of room temperature and amine (ammonium) solution of temperature-responsive polyacrylate analog copolymer, and dosage is 2g/L dirty
Mud is uniformly mixed；
(2) it is continuously added to acid into reactor tank second level mixing section while stirring, enters conversion zone later and react 15min, makes poly- third
The water soluble group of olefin(e) acid ester copolymer sloughs amine (ammonium) base by ion exchange, and formation-COOH reduces copolymer
Solubility makes copolymer molecule sufficiently be precipitated and be combined with mud granule by van der Waals interaction absorption, sludge pH after reaction
It is 4.6；
(3) sludge is pumped into preheating can by sludge pump after reacting, and gravity flow enters heating tank and heated after being preheated by heat exchange, makes
Temperature is increased to 10 DEG C of Tg or more of polyacrylate copolymer, crimps copolymer molecule chain movement, keeps the temperature 5min, utilizes heat
Effect makes reunites together with the copolymer molecule chain movement curling drive mud granule that mud granule adsorbs, and contraction distortion passes through
The hydrophobic groupings such as methyl, ethyl, ester group in polyacrylate copolymer improve the hydrophobicity of mud granule, improve concentration effect
Fruit；
(4) dirty overflow enters air floatation machine progress floatation thickening in heating tank, and by thickened sludge is discharged at the top of air floatation machine, after air bearing
The water being concentrated out, for the sludge after pre- thermal response, is recycled thermal energy, then drained by reflux water pump continuous backflow to heat exchange tank
Waste water treatment system；
(5) thickened sludge is cooled below temperature-responsive polyacrylate copolymer Tg hereinafter, being transformed into copolymer
Glassy state hardens hole between the mud granule that rear support is formed, and reduces sludge specific resistance, then removes filtering means dehydration.
Rear textile printing and dyeing sludge is further concentrated pre-concentration through this method for 24 hours, and volume reduction is obvious, after concentration
Sludge shows that compared with raw sewage, rate of water loss is obviously accelerated through vacuum filtration dehydration test result, reaches identical sludge and contains
Water rate, dewatering time can be shorten within original 20%, 90% or more sludge specific resistance decline.Specific sludge reduction and sludge ratio
Test result is as follows shown in table for resistance:
Sludge condensation reduction and resistivity test result
The foregoing is only a preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto, and it is any
Those skilled in the art in the technical scope disclosed by the present invention, according to the technical scheme of the invention and its inventive conception
It is subject to equivalent substitution or change, should be covered by the protection scope of the present invention.
Claims (8)
1. a kind of method of continuous Floatation Thickening Sludge, which is characterized in that add pH and temperature-responsive polypropylene into sludge
Acid ester copolymer, its reaction is precipitated in response pH variation, then is changed to the response of temperature by temperature change with copolymer molecule chain
Become its physical state, realize the concentration of sludge, and reduces sludge specific resistance, comprising the following steps:
(1) sludge after pre-concentration is pumped into reactor tank, continuously adds vitrifying in proportion into reactor tank level-one mixing section
Temperature (Tg) is higher than the pH of room temperature and amine (ammonium) solution of temperature-responsive polyacrylate analog copolymer, is uniformly mixed；
(2) it is continuously added to acid into reactor tank second level mixing section while stirring, enters conversion zone later and react 5-20min, makes to gather
The water soluble group of acrylate copolymer sloughs amine (ammonium) base by ion exchange, and formation-COOH reduces copolymer
Solubility, make copolymer molecule be sufficiently precipitated and with mud granule by van der Waals interaction absorption combined, sludge after reaction
PH is 4-6；
(3) sludge is pumped into preheating can by sludge pump after reacting, and gravity flow enters heating tank and heated after being preheated by heat exchange, makes
Temperature is increased to Tg or more the 5-20 DEG C of polyacrylate copolymer, changes its physical state, rolls up copolymer molecule chain movement
Song keeps the temperature 5-20min, so that the copolymer molecule chain movement adsorbed with mud granule curling is driven mud granule one using heat effect
It rises and reunites, contraction distortion improves mud granule by hydrophobic groupings such as methyl, ethyl, ester groups in polyacrylate copolymer
Hydrophobicity, improve concentrated effect；
(4) dirty overflow enters air floatation machine progress floatation thickening in heating tank, and by thickened sludge is discharged at the top of air floatation machine, after air bearing
The water being concentrated out, for the sludge after pre- thermal response, is recycled thermal energy, then drained by reflux water pump continuous backflow to heat exchange tank
Waste water treatment system；
(5) concentration paste sludge is cooled below pH and temperature-responsive polyacrylate copolymer Tg hereinafter, making to be copolymerized
Object reverts to glassy state, and hole between the mud granule that hardening rear support is formed reduces sludge specific resistance, then removes filtering means dehydration.
2. a kind of method of continuous concentration organic sludge according to claim 1, which is characterized in that in the step (1)
PH and temperature-responsive polyacrylate copolymer is soft by esters of acrylic acid, hard monomer or non-acrylic compounds hard monomer are copolymerized shape
At by the Tg of monomer mole ratio control copolymer higher than room temperature.
3. a kind of method of continuous concentration organic sludge according to claim 1, which is characterized in that in the step (1)
PH and temperature-responsive polyacrylate copolymer number-average molecular weight be not less than 5000, weight average molecular weight be not less than 8000.
4. a kind of method of continuous Floatation Thickening Sludge according to claim 1, which is characterized in that in the step (2)
Acid be inorganic acid or organic acid, if organic acid, its degree of ionization should be greater than carboxylic acid in temperature-responsive polyacrylate copolymer
The degree of ionization of base, preferably inorganic acid.
5. a kind of method of continuous Floatation Thickening Sludge according to claim 1, which is characterized in that in the step (3)
Preheating can heating use board-like or pipe type heat transfer mode.
6. a kind of method of continuous Floatation Thickening Sludge according to claim 1, which is characterized in that in the step (3)
Heating tank heating using electric heating, steam heating, any indirect heating manner in heat-conducting oil heating or its combined heat side
Formula.
7. a kind of method of continuous Floatation Thickening Sludge according to claim 1, which is characterized in that in the step (4)
Air floatation machine using any one of conventional gas distribution air floatation machine, jet air float machine or dissolved gas floatator, preferably dissolved gas floatator.
8. a kind of method of continuous Floatation Thickening Sludge according to claim 1, which is characterized in that in the step (5)
Filtering means dehydration refer to using vacuum filtration or mechanism filter-pressing dewatering type any or its combined dehydration by the way of.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811552068.5A CN109368984A (en) | 2018-12-18 | 2018-12-18 | A kind of method of continuous Floatation Thickening Sludge |
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| CN201811552068.5A CN109368984A (en) | 2018-12-18 | 2018-12-18 | A kind of method of continuous Floatation Thickening Sludge |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51126969A (en) * | 1975-04-30 | 1976-11-05 | Kurita Water Ind Ltd | A method of dehydrating activated sludge |
| JPS58131200A (en) * | 1982-01-29 | 1983-08-04 | Unitika Ltd | Treatment of sludge |
| CN105084576A (en) * | 2014-05-05 | 2015-11-25 | 青岛大学 | Method for treating high-concentration water-based ink waste liquid and dehydrating sludge in high-concentration water-based ink waste liquid |
| CN106608709A (en) * | 2015-10-27 | 2017-05-03 | 禾华环保科技（上海）有限公司 | Dehydrating agent for sludge, and preparation and application thereof |
| WO2018022352A1 (en) * | 2016-07-25 | 2018-02-01 | Dow Global Technologies Llc | Acoustic mixing for flocculant addition to mineral suspensions |
-
2018
- 2018-12-18 CN CN201811552068.5A patent/CN109368984A/en not_active Withdrawn
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51126969A (en) * | 1975-04-30 | 1976-11-05 | Kurita Water Ind Ltd | A method of dehydrating activated sludge |
| JPS58131200A (en) * | 1982-01-29 | 1983-08-04 | Unitika Ltd | Treatment of sludge |
| CN105084576A (en) * | 2014-05-05 | 2015-11-25 | 青岛大学 | Method for treating high-concentration water-based ink waste liquid and dehydrating sludge in high-concentration water-based ink waste liquid |
| CN106608709A (en) * | 2015-10-27 | 2017-05-03 | 禾华环保科技（上海）有限公司 | Dehydrating agent for sludge, and preparation and application thereof |
| WO2018022352A1 (en) * | 2016-07-25 | 2018-02-01 | Dow Global Technologies Llc | Acoustic mixing for flocculant addition to mineral suspensions |
Non-Patent Citations (2)
| Title |
|---|
| 冯孝中等: "《高分子材料》", 28 February 2007, 哈尔滨工业大学出版社 * |
| 王淑荣等: "《染整废水处理》", 30 September 2005, 中国纺织出版社 * |
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Address after: 266071 No. 7 East Hongkong Road, Laoshan District, Shandong, Qingdao Applicant after: QINGDAO University Address before: 266071 Ningxia Road, Shandong, China, No. 308, No. Applicant before: QINGDAO University |
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Application publication date: 20190222 |