CN102795755A - Sludge deep dehydrating system and sludge deep dehydrating method - Google Patents
Sludge deep dehydrating system and sludge deep dehydrating method Download PDFInfo
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- CN102795755A CN102795755A CN201110153981XA CN201110153981A CN102795755A CN 102795755 A CN102795755 A CN 102795755A CN 201110153981X A CN201110153981X A CN 201110153981XA CN 201110153981 A CN201110153981 A CN 201110153981A CN 102795755 A CN102795755 A CN 102795755A
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- water ratio
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- 239000010802 sludge Substances 0.000 title claims abstract description 87
- 238000000034 method Methods 0.000 title claims abstract description 38
- 230000018044 dehydration Effects 0.000 claims abstract description 60
- 238000006297 dehydration reaction Methods 0.000 claims abstract description 60
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 42
- 239000000126 substance Substances 0.000 claims description 12
- 239000003795 chemical substances by application Substances 0.000 claims description 11
- 238000005189 flocculation Methods 0.000 claims description 11
- 230000016615 flocculation Effects 0.000 claims description 11
- 239000003607 modifier Substances 0.000 claims description 11
- 230000003750 conditioning effect Effects 0.000 claims description 10
- 230000032258 transport Effects 0.000 claims description 4
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims description 2
- 235000011941 Tilia x europaea Nutrition 0.000 claims description 2
- 239000004571 lime Substances 0.000 claims description 2
- 238000012546 transfer Methods 0.000 claims description 2
- 238000005265 energy consumption Methods 0.000 abstract description 6
- 239000010865 sewage Substances 0.000 abstract description 6
- 238000005496 tempering Methods 0.000 abstract 2
- 239000008394 flocculating agent Substances 0.000 abstract 1
- 238000002203 pretreatment Methods 0.000 abstract 1
- 208000005156 Dehydration Diseases 0.000 description 44
- 238000012545 processing Methods 0.000 description 6
- 238000001914 filtration Methods 0.000 description 5
- 239000010801 sewage sludge Substances 0.000 description 5
- 239000007788 liquid Substances 0.000 description 2
- 238000012806 monitoring device Methods 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 239000004743 Polypropylene Substances 0.000 description 1
- 229920000297 Rayon Polymers 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 150000001408 amides Chemical class 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 235000011837 pasties Nutrition 0.000 description 1
- -1 polypropylene Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
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- Treatment Of Sludge (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
Abstract
The invention provides a sludge deep dehydrating system and a sludge deep dehydrating method, which have the advantages of low cost, low energy consumption and capability of dehydrating sewage and sludge to the lower water content for one time. The sludge deep dehydrating method comprises the following steps of: carrying out sludge pre-treatment to obtain sludge with the water content in a certain range; carrying out sludge tempering treatment to add a flocculating agent into the sludge and reduce a specific resistance value of the sludge; and carrying out mechanical dehydrating treatment to carry out mechanical dehydration on the sludge after the sludge tempering treatment so as to obtain a dehydrated mud cake.
Description
Technical field
The present invention relates to the deeply dehydrating sludge field, relate in particular to a kind of deeply dehydrating sludge system and deep dehydration method for sludge.
Background technology
Mostly traditional sludge dewatering treatment is only to adopt mechanical dewatering equipment, mud is carried out so-called mechanical dehydration handle.The mud that carried out mechanical dehydration processing first can be controlled at the water ratio of dewatered sludge about 78~85%, but this does not reach the ideal effect that carries out sludge dewatering treatment far away.And because the mud of this water ratio is pasty state, still be solid-liquid mixings shape, be not easy to stack, transport, and exist percolate extremely hard to manage, can not directly fill up, be prone to the shortcomings such as follow-up utilization again that cause environmental pollution and can't carry out mud.
Given this, in the prior art, carried out a series of research, proposed twice pressing processed method, natural wind dry method, centrifugal dehydration treatment method etc. to this dewatered sludge that carried out mechanical dehydration processing first.But; These are to the treatment process of carrying out through the dewatered sludge after mechanical dehydration is handled first; Exist all that the energy consumption that secondary treatment causes increases, the operational cycle prolongs and the problem of effective ingredient loss etc., directly cause the increase of processed cost.And, because mostly dewatered sludge be to be formed by the set of cotton-shaped colloid, in the time of between the water ratio in the mud drops to 55%~65%, can form one and be called the state of " viscose glue phase region ", be difficult to further detach moisture the mud under this state again.Therefore, handle under the background that causes energy consumption increase, cost raising, cycle stretch-out at second dehydration, the mud dewatering method of secondary treatment does not obviously have the advantage that more voluminous industry is used.
Summary of the invention
The present invention is exactly in view of the above problems and proposes, its purpose be to provide a kind of low cost, less energy-consumption, disposable with the sewage sludge deep dehydration to deeply dehydrating sludge system and deep dehydration method for sludge than low-water-content.
Deep dehydration method for sludge of the present invention comprises: mud is handled in earlier stage, obtains water ratio mud within the specific limits; The mud modifier treatment is added flocculation agent to above-mentioned mud, reduces the specific impedance value of above-mentioned mud; And the mechanical dehydration processing, the above-mentioned mud after above-mentioned mud modifier treatment is carried out mechanical dehydration, obtain dehydrated sludge cake.
According to deep dehydration method for sludge of the present invention; Through the mud modifier treatment is combined with the mechanical dehydration method; Can with water ratio below the disposable dehydration to 55% of the mud about 93%~98%, can the water ratio of dehydrated sludge cake be controlled at 55%~38% basically.
In the deep dehydration method for sludge of the present invention, preferred, the part of the moisture that above-mentioned mechanical dehydration is deviate from handling turns back to during above-mentioned mud handles in earlier stage, regulates the water ratio of above-mentioned mud.Another part of above-mentioned moisture gets into Sewage treatment systems.Handle according to this, can utilize the moisture of from mud, deviating from once more, realize the utilization again of moisture.
In the deep dehydration method for sludge of the present invention, preferred, also comprise dehydrated sludge cake check processing, check the water ratio of above-mentioned dehydrated sludge cake.
In the deep dehydration method for sludge of the present invention, preferred, during above-mentioned mud is handled in earlier stage, the water ratio of above-mentioned mud is adjusted to 93%~98%.
In the deep dehydration method for sludge of the present invention, preferred, above-mentioned flocculation agent contains SEPIGEL 305.
In the deep dehydration method for sludge of the present invention, preferred, in the above-mentioned mud modifier treatment, above-mentioned specific impedance value is controlled at 0.4 * 10
9~0.7 * 10
9Cm/g.
In the deep dehydration method for sludge of the present invention, preferred, the water ratio of above-mentioned dehydrated sludge cake is 55%~38%.
The present invention also provides a kind of deeply dehydrating sludge system that is used for above-mentioned deep dehydration method for sludge, and this deeply dehydrating sludge system comprises: mud treatment unit in early stage obtains water ratio mud within the specific limits; The mud modifying device, it links to each other via dredging tube with above-mentioned mud treatment unit in early stage, to from above-mentioned mud in earlier stage the above-mentioned mud that transports of treatment unit carry out chemical conditioning; And the mechanical dehydration device, it links to each other via modified mud transfer lime with above-mentioned mud modifying device, the above-mentioned mud behind above-mentioned chemical conditioning is carried out mechanical dehydration handle, and obtains dehydrated sludge cake.
In the deeply dehydrating sludge of the present invention system; Preferably; Above-mentioned mechanical dehydration device links to each other with said mud treatment unit in early stage via the backflow hydraulic pipe; Above-mentioned mechanical dehydration is handled the part of the moisture that obtains, and is transported in the above-mentioned mud treatment unit in early stage via the backflow hydraulic pipe, regulates the water ratio of above-mentioned mud.
In the deeply dehydrating sludge of the present invention system, preferred, also comprise: the dehydrated sludge cake verifying attachment, check the water ratio of above-mentioned dehydrated sludge cake.
According to the present invention, can provide a kind of low cost, less energy-consumption, disposable with the sewage sludge deep dehydration to deeply dehydrating sludge system and deep dehydration method for sludge than low-water-content.
Description of drawings
Fig. 1 is the structural representation of expression deeply dehydrating sludge of the present invention system.
Embodiment
Deep dehydration method for sludge of the present invention possesses mud to be handled in earlier stage, and mud modifier treatment and mechanical dehydration are handled.Fig. 1 is the schematic representation of apparatus of carrying out above-mentioned processing respectively.
During mud is handled in earlier stage; Through mud treatment unit in early stage; Preset the water ratio 93%~99.2% or the mud of high-moisture more, the mud that is stored in the mud concentration basin that treatment unit possesses early stage etc. leaves standstill in the container, regulates; Obtain the mud of 93%~98% water ratio, be preferably the mud of water ratio 98%.At this moment, for the convenience of handling, save the process of conveying, also can directly handle to the mud of generations such as sewage work, the storing device that mud is original leaves standstill container as mud.For example, the primary sludge storage pool among Fig. 1 as concentration basin, and is omitted concentration basin.
In the mud modifier treatment, utilize the mud modifying device, the mud of the water ratio 93%~98% that obtains during mud is handled in earlier stage; Add chemicals such as flocculation agent; Break the colloidal structure of mud, reduce the specific impedance value of mud, make the moisture in the mud be able to sufficient release.Mud in mud modifying device and the mud treatment unit in early stage leaves standstill container and links to each other, to leave standstill the additives such as mud interpolation flocculation agent that container transport is come from mud, carries out chemical conditioning.
When the mud that above-mentioned specific impedance value refers to unit mass filters under certain pressure, the resistance on the unit filtration area.The proportional example relation of the complexity of specific impedance value and sludge dewatering, promptly the specific impedance value of mud is more little, and this mud just discharges its contained moisture more easily, reduces the difficulty of dehydration, realizes solid-liquid separation easily.The researchist finds through test, and the specific impedance value of mud of not passing through chemical conditioning is all 1.0 * 10
9More than the cm/g, be difficult to dewater again.And the specific impedance value of sewage mud can reach 2.47 * 10
9Cm/g without modified, can not reach water ratio below 60% basically.In the mud modifier treatment, preferred, the specific impedance value of mud is controlled at (0.5~0.9) * 10
9About cm/g, be more preferably and be controlled at (0.4~0.7) * 10
9About cm/g.
This flocculation agent can contain SEPIGEL 305, also can be other chemicals that can reduce the specific impedance value of mud.If contain the flocculation agent of SEPIGEL 305, then the weight ratio of optimization polypropylene acid amides is 4.38~5.33 ‰.
Handle at mechanical dehydration, the mud that will pass through chemical conditioning is transported in the filtering equipment of full-automatic plate-and-frame filter press etc., carries out mechanical dehydration to handle, and obtains the dehydrated sludge cake of water ratio 55%~38%, realizes separating of moisture and mud cake.Dehydrated sludge cake is seen off through e Foerderanlages such as travelling belts.So, the dehydrated sludge cake verifying attachment can also be set, the water ratio of check dehydrated sludge cake, whether the water ratio that detects dehydrated sludge cake has reached desired value, realizes the real-time monitoring of dehydrated sludge cake water ratio.
The mechanical dehydration device connects above-mentioned mud treatment unit in early stage via the backflow hydraulic pipe.Handle the moisture obtain through mechanical dehydration, a part gets into Sewage treatment systems via conduit, handles again, and another part leaves standstill in the container via the mud that the backflow hydraulic pipe is transported to concentration basin etc., regulates the water ratio that mud leaves standstill the mud in the container.For convenient processing and detection; Monitoring mud also can be set leave standstill the moisture percentage in sewage sludge monitoring device of the moisture percentage in sewage sludge in the container, and the variable valve of regulating the moisture operational throughput according to the detected result of moisture percentage in sewage sludge monitoring device is set on the backflow hydraulic pipe.
Below, the specific embodiment of deep dehydration method for sludge of the present invention is described.
Embodiment 1
At first, collect water ratio and be 1000 kilograms in 93% mud, add 7 kilograms flocculation agent, carry out chemical conditioning, obtain the mud after modified, recording its specific impedance value is 0.69 * 10
9Cm/g.Then, will pass through in the filtering equipment that modified mud is transported to plate-and-frame filter press etc., and carry out mechanical dehydration and handle, and obtain dehydrated sludge cake, the water ratio that records this dehydrated sludge cake is 50%.
Embodiment 2
Collect 1000 kilograms in the mud of water ratio 95%, add 9 kilograms flocculation agent, carry out chemical conditioning, obtain the mud after modified, recording its specific impedance value is 0.5 * 10
9Cm/g.To pass through in the filtering equipment that modified mud is transported to plate-and-frame filter press etc., and carry out mechanical dehydration and handle, and obtain dehydrated sludge cake, the water ratio that records this dehydrated sludge cake is 45%.
Embodiment 3
Collect 1000 kilograms in the mud of water ratio 98%, add 10 kilograms flocculation agent, carry out chemical conditioning, obtain the mud after modified, recording its specific impedance value is 0.45 * 10
9Cm/g.To pass through in the filtering equipment that modified mud is transported to plate-and-frame filter press etc., and carry out mechanical dehydration and handle, and obtain dehydrated sludge cake, the water ratio that records this dehydrated sludge cake is 42%.
According to deep dehydration method for sludge of the present invention; Through combining with mud modifier treatment and mechanical dehydration method; Can with water ratio below the disposable dehydration to 55% of the mud about 93%~98%, can the water ratio of dehydrated sludge cake be controlled at 55%~38% basically.Compared with prior art; This method is not to the dual-spectrum process of mud; Reduce required energy consumption, cost and the cycle of secondary treatment effectively, and greatly reduced water ratio, reduced the sludge volume amount; Storage space and transportation cost can be practiced thrift, the cost of mud subsequent disposal can be reduced simultaneously.
Through implement present method in mud country of origin such as sewage works, can also reduce the generation of mud from the source, be beneficial to energy-saving and emission-reduction.
As stated, specified embodiments of the invention, but the present invention is not limited thereto, the various changes of in the scope of technical scheme of the present invention, carrying out also belong to scope of the present invention.
Claims (10)
1. a deep dehydration method for sludge is characterized in that, comprising:
Mud is handled in earlier stage, obtains water ratio mud within the specific limits;
The mud modifier treatment is added flocculation agent to said mud, reduces the specific impedance value of said mud; And
Mechanical dehydration is handled, and the said mud after said mud modifier treatment is carried out mechanical dehydration, obtains dehydrated sludge cake.
2. deep dehydration method for sludge according to claim 1 is characterized in that:
The part of the moisture that said mechanical dehydration is deviate from handling turns back to during said mud handles in earlier stage, regulates the water ratio of said mud.
3. deep dehydration method for sludge according to claim 1 and 2 is characterized in that, also comprises: the dehydrated sludge cake check is handled, and checks the water ratio of said dehydrated sludge cake.
4. deep dehydration method for sludge according to claim 1 and 2 is characterized in that:
During said mud is handled in earlier stage, the water ratio of said mud is adjusted to 93%~98%.
5. deep dehydration method for sludge according to claim 1 and 2 is characterized in that:
Said flocculation agent contains SEPIGEL 305.
6. deep dehydration method for sludge according to claim 1 is characterized in that:
In the said mud modifier treatment, said specific impedance value is controlled at 0.4 * 10
9~0.7 * 10
9Cm/g.
7. according to each described deep dehydration method for sludge in the claim 1~4, it is characterized in that:
The water ratio of said dehydrated sludge cake is 55%~38%.
8. deeply dehydrating sludge system that is used for each described deep dehydration method for sludge of claim 1~7 is characterized in that this system comprises:
Mud treatment unit in early stage obtains the mud of water ratio in certain scope;
The mud modifying device, it links to each other via dredging tube with said mud treatment unit in early stage, to from said mud in earlier stage the said mud that transports of treatment unit carry out chemical conditioning; And
The mechanical dehydration device, it links to each other via modified mud transfer lime with said mud modifying device, the said mud behind said chemical conditioning is carried out mechanical dehydration handle, and obtains dehydrated sludge cake.
9. deeply dehydrating sludge according to claim 8 system is characterized in that:
Said mechanical dehydration device links to each other with said mud treatment unit in early stage via the backflow hydraulic pipe; Said mechanical dehydration is handled the part of the moisture that obtains; Be transported in the said mud treatment unit in early stage via said backflow hydraulic pipe, regulate the water ratio of said mud.
10. according to Claim 8 or 9 described deeply dehydrating sludge systems, it is characterized in that, also comprise:
The dehydrated sludge cake verifying attachment is checked the water ratio of above-mentioned dehydrated sludge cake.
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CN201110153981XA CN102795755A (en) | 2011-05-27 | 2011-05-27 | Sludge deep dehydrating system and sludge deep dehydrating method |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105481222A (en) * | 2016-01-18 | 2016-04-13 | 江苏绿威环保科技有限公司 | Electroosmosis dehydration system |
CN110590122A (en) * | 2019-10-17 | 2019-12-20 | 湖北玉鑫新型墙材有限公司 | Method for circularly applying sludge wastewater to sludge dewatering |
CN114751619A (en) * | 2021-11-01 | 2022-07-15 | 青岛蓝博环境科技有限公司 | Method and equipment for two-stage integrated deep dehydration of municipal sludge |
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JPS61257300A (en) * | 1985-05-08 | 1986-11-14 | Ishikawajima Harima Heavy Ind Co Ltd | Sludge dewatering equipment |
US5624550A (en) * | 1992-08-13 | 1997-04-29 | Chemical Grouting Co., Ltd. | Process for treating sludge and system for the same |
CN1962496A (en) * | 2006-11-15 | 2007-05-16 | 广州普得环保设备有限公司 | Sludge deep dehydration method |
CN101367597A (en) * | 2008-09-17 | 2009-02-18 | 广州绿由工业弃置废物回收处理有限公司 | Flocculating agent for sludge dewatering and sludge dewatering method |
CN101691272A (en) * | 2009-10-01 | 2010-04-07 | 厦门水务集团有限公司 | Sludge dewatering method |
CN202054726U (en) * | 2011-05-27 | 2011-11-30 | 广东绿由环保科技股份有限公司 | Deep dehydration system for sludge |
-
2011
- 2011-05-27 CN CN201110153981XA patent/CN102795755A/en active Pending
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
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JPS61257300A (en) * | 1985-05-08 | 1986-11-14 | Ishikawajima Harima Heavy Ind Co Ltd | Sludge dewatering equipment |
US5624550A (en) * | 1992-08-13 | 1997-04-29 | Chemical Grouting Co., Ltd. | Process for treating sludge and system for the same |
CN1962496A (en) * | 2006-11-15 | 2007-05-16 | 广州普得环保设备有限公司 | Sludge deep dehydration method |
CN101367597A (en) * | 2008-09-17 | 2009-02-18 | 广州绿由工业弃置废物回收处理有限公司 | Flocculating agent for sludge dewatering and sludge dewatering method |
CN101691272A (en) * | 2009-10-01 | 2010-04-07 | 厦门水务集团有限公司 | Sludge dewatering method |
CN202054726U (en) * | 2011-05-27 | 2011-11-30 | 广东绿由环保科技股份有限公司 | Deep dehydration system for sludge |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105481222A (en) * | 2016-01-18 | 2016-04-13 | 江苏绿威环保科技有限公司 | Electroosmosis dehydration system |
CN110590122A (en) * | 2019-10-17 | 2019-12-20 | 湖北玉鑫新型墙材有限公司 | Method for circularly applying sludge wastewater to sludge dewatering |
CN114751619A (en) * | 2021-11-01 | 2022-07-15 | 青岛蓝博环境科技有限公司 | Method and equipment for two-stage integrated deep dehydration of municipal sludge |
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Application publication date: 20121128 |