CN211035588U - Shield mud dewatering device - Google Patents
Shield mud dewatering device Download PDFInfo
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- CN211035588U CN211035588U CN201921104618.7U CN201921104618U CN211035588U CN 211035588 U CN211035588 U CN 211035588U CN 201921104618 U CN201921104618 U CN 201921104618U CN 211035588 U CN211035588 U CN 211035588U
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Abstract
A shield mud dewatering device comprises a power supply, a negative plate with holes connected with the power supply, a flat ceramic membrane closely adjacent to the negative plate with holes, a mud storage tank, an anode plate, a vacuum water collecting device, a back washing device, a purging and aerating device and a conical clamping groove for storing solid matters; the flat ceramic membrane and the negative plate with holes form a cathode membrane together, the upper end of the flat ceramic membrane is connected with a vacuum water collecting device, the vacuum water collecting device is used for collecting collected, electrolyzed and clarified filtrate flowing from the negative plate with holes and the flat ceramic membrane during dehydration operation, and the lower end of the flat ceramic membrane is connected with a backwashing device used for backwashing the flat ceramic membrane to prevent soil particles from being blocked through a pipeline; the bottom of the slurry storage tank is provided with a conical clamping groove for storing solids and a blowing aeration device, the conical clamping groove is used for collecting positive ion soil particles accumulated near the anode plate during dehydration operation, and the blowing aeration device is used for blowing high-pressure gas to stir slurry to roll. Stirring the slurry to roll, and preventing the pollution of the flat ceramic membrane and the plate electrode.
Description
Technical Field
The invention relates to the field of slurry dehydration, in particular to a shield slurry dehydration device which is mainly used for treating slurry generated in the process of pipe jacking shield.
Background
In underground engineering construction, the methods such as cast-in-situ bored piles, underground continuous walls, slurry balance shield tunneling and the like use bentonite slurry to support the wall of a groove, a working surface and the like in construction, a large amount of waste slurry is generated in slurry circulation, and once the waste slurry is not transported smoothly, the construction progress is influenced. The composition and the property of the slurry are different from those of municipal slurry, the slurry is a suspension liquid which mainly comprises clay minerals and contains a certain amount of fine mud particles, the natural sedimentation and direct dehydration effects are poor, and if the slurry is not properly treated, the slurry is easy to cause the hazards of environmental pollution, water quality damage, municipal pipeline blockage and the like. It is therefore often necessary to subject the waste sludge to an on-site "in situ" dewatering process.
In the past, on-site precipitation drying of slurry, outward transportation of a canned car (slurry car) and the like are mainly adopted, but the problems of long treatment period, high cost and the like exist.
Currently, a membrane filtration method, a centrifugation method, a screw extrusion method, a rotary extrusion method, an electroosmosis method, and the like are commonly used. Wherein, the membrane filtration method is only generally applicable to slurry with the solid content of less than 1.5 percent; the centrifugal method has large energy consumption, needs to add chemical flocculant, has relatively large noise, expensive accessories and large repair difficulty; the spiral pressure method has small treatment capacity, large occupied space, low solid content after treatment and large chemical flocculating agent amount; the rotary extrusion method only aims at the slurry with high fiber content, and has good adaptability, low processing capacity and high equipment cost.
The solid content of the supernatant obtained by the mechanical method of slurry dehydration is large, the blockage of a supernatant return pipe is easily caused, the abrasion of a main machine is serious, and in a pipeline of the automatic flocculant dosing device, the caking and silting on a stirrer waste time and labor in cleaning. At present, the electroosmosis dehydration method is immature in technology, relatively high in energy consumption, high in solid content (10-20%) required in slurry treatment, small in treatment amount and high in cost.
Furthermore, in existing treatment facilities, care is often taken to remove only the free water from the slurry, and the treatment of the capillary water is ignored.
Disclosure of Invention
The invention provides a simple, effective and low-cost shield slurry dewatering device, which can generate a large amount of shield slurry (slurry and flocculating agent) in the methods of cast-in-situ bored piles, underground continuous walls, slurry balance shield tunnel tunneling and the like, and can treat free water and capillary water in the slurry by using an electrolysis-vacuum combined filtration process so as to achieve the purpose of slurry reduction treatment and realize shield slurry reduction treatment.
The technical scheme adopted by the invention for solving the problems is as follows: the electrolysis-vacuum combined slurry filtering dehydration is characterized in that sludge-water separation is realized under the action of an electric field, and the obtained clarified filtrate is recycled, so that the electrodialysis dehydrator mainly comprises a power supply 1, a porous cathode plate 2 connected with the power supply 1, a flat ceramic membrane 3 adjacent to the porous cathode plate 2, a slurry storage tank 4, an anode plate 5, a vacuum water collecting device 6, a back washing device 7, a purging aeration device 8 and a solid storage conical clamping groove 9, wherein the porous cathode plate 2 is connected with the negative pole of the power supply 1, and the anode plate 5 is connected with the positive pole of the power supply 1; the flat ceramic membrane 3 and the negative plate with holes form a cathode membrane together, the upper end of the flat ceramic membrane 3 is connected with a vacuum water collecting device 6, the vacuum water collecting device 6 is used for collecting collected electrolytic clarification filtrate flowing from the negative plate with holes 2 and the flat ceramic membrane 3 during dehydration operation, and the lower end of the flat ceramic membrane 3 is connected with a back washing device 7 used for back washing the flat ceramic membrane 3 to prevent soil particles from being blocked through a pipeline; the bottom of the slurry storage tank 4 is provided with a solid storage conical clamping groove 9 and a purging and aerating device 8, the solid storage conical clamping groove 9 is used for collecting positive ion soil particles stored near the anode plate 5 during dehydration, and the purging and aerating device 8 is used for blowing high-pressure gas to stir slurry to roll.
Alternatively, the positive pole of the power supply 1 is connected to the anode plate 5 and the negative pole of the power supply 1 is connected to the perforated cathode plate 2.
Alternatively, the anode plate 5 is an iron or aluminum plate, the perforated cathode plate 2 is a perforated iron or aluminum plate, and the perforated cathode plate 2 and the flat ceramic membrane 3 together form a cathode membrane
Alternatively, the perforated cathode plates 2 and anode plates 5 are arranged in an array.
Optionally, a vacuum water collecting device 6 is connected to the flat ceramic membrane 3 through a vacuum pump and a pipeline for collecting the clarified filtrate.
Optionally, a back-flushing device 7 is connected to the lower end of the flat ceramic membrane 3 through a pipe for back-flushing it with fresh water or high-pressure air.
Optionally, a cone-shaped solid storage slot 9 is detachably mounted below the anode plate 5.
Alternatively, the flat ceramic membrane 3, the perforated cathode plate 2 and the anode plate 5 are all arranged upright at the bottom of the slurry storage tank 4.
Optionally, a horizontal-tank type purge aeration device 8 is arranged at the bottom of the slurry storage tank 4 to generate high-pressure shear gas flow for purging along the cut surfaces of the perforated cathode plate 2 and anode plate 5.
Optionally, more than two groups of the flat ceramic membrane 3, the perforated cathode plate 2 and the anode plate are respectively matched with each other.
Optionally, the vacuum water collecting device 6 comprises a vacuum water collecting tank and a vacuum pump which are communicated with the flat ceramic membrane 3 through a pipeline, and the vacuum water collecting tank and the vacuum pump penetrate through the cathode plate 2 with holes to flow into the flat ceramic membrane 3 and finally converge into the vacuum water collecting tank.
Optionally, high-pressure shearing airflow, namely the blowing aeration 8, is introduced to the bottom of the slurry storage tank 4 along the wall of the tank, so that the slurry is stirred to roll, and the pollution of the flat ceramic membrane and the electrode plate is prevented.
The vacuum water collecting device 6 is connected with the bottom of the flat ceramic membrane 3 through a pipeline, and clear filtrate is collected by utilizing negative pressure generated by vacuumizing. The anode plate 5 gathers soil particles in the electrolytic process, and a solid object storage conical clamping groove 9 for detachably storing the soil particles is arranged at the bottom of the anode plate, so that the soil particles can be periodically removed.
Compared with the prior art, the invention has the following beneficial effects:
(1) the system is suitable for purifying the slurry in projects such as slurry balance shield, diaphragm wall, pile foundation and the like of a circulating drilling process, is favorable for controlling the slurry performance, enhancing the hole forming quality and the working efficiency, comprehensively supporting and ensuring the safe and smooth operation of tunneling equipment, improving the recycling of the slurry, not only saving the construction cost, but also reducing the slurry discharge and reducing the environmental pollution, and is necessary equipment for economic, efficient and environment-friendly construction.
(2) By the electrolysis-vacuum combined filtering process, capillary water and free water in the slurry are removed simultaneously, and the slurry is subjected to reduction treatment, so that the slurry treatment efficiency is improved, and the reduction treatment effect is enhanced.
3) Biochemical sludge with high solid content (5-20%) can be treated, slurry drying procedures such as a plate-and-frame filter press and a screw stacking machine are simplified, and energy consumption is low;
(4) due to the array arrangement, the treatment capacity is large by designing along with the size of the mud sedimentation tank.
Drawings
The invention is further described below with reference to the accompanying drawings.
FIG. 1 is a schematic view of an overall apparatus;
FIG. 2 is a schematic view of an electrode array arrangement;
fig. 3 is a schematic view of a tapered slot for storing solids for storing slurry.
Reference numerals: 1. a power source; 2. a negative plate with holes; 3. a flat ceramic membrane; 4. a slurry storage tank; 5. an anode plate; 6. a vacuum water collection device; 7. a backwashing device; 8. purging the aeration device; 9. and a tapered slot for storing solid objects.
Detailed Description
The invention provides a simple, effective and low-cost shield slurry dehydration device, wherein the electrolysis-vacuum combined slurry filtration dehydration is actually to realize mud-water separation under the action of an electric field, and the obtained clarified filtrate is recycled, so that an electrodialysis dehydrator mainly comprises a power supply 1, a porous cathode plate 2 connected with the power supply 1, a flat ceramic membrane 3 adjacent to the porous cathode plate 2, a slurry storage tank 4, an anode plate 5, a vacuum water collecting device 6, a back washing device 7, a purging aeration device 8 and a solid storage conical clamping groove 9, wherein the porous cathode plate 2 is connected with the negative electrode of the power supply 1, and the anode plate 5 is connected with the positive electrode of the power supply 1; the flat ceramic membrane 3 and the negative plate with holes form a cathode membrane together, the upper end of the flat ceramic membrane 3 is connected with a vacuum water collecting device 6, the vacuum water collecting device 6 is used for collecting collected electrolytic clarification filtrate flowing from the negative plate with holes 2 and the flat ceramic membrane 3 during dehydration operation, and the lower end of the flat ceramic membrane 3 is connected with a back washing device 7 used for back washing the flat ceramic membrane 3 to prevent soil particles from being blocked through a pipeline; the bottom of the slurry storage tank 4 is provided with a solid storage conical clamping groove 9 and a purging and aerating device 8, the solid storage conical clamping groove 9 is used for collecting positive ion soil particles stored near the anode plate 5 during dehydration, and the purging and aerating device 8 is used for blowing high-pressure gas to stir slurry to roll.
More specifically, a flat ceramic membrane 3, a perforated cathode plate 2 and an anode plate 5 are all vertically fixed to the bottom of a slurry storage tank 4, connecting the respective pipes to a vacuum water collecting device 6.
Alternatively, the power supply 1 may be a dc power supply connected to a battery, or may be an ac rectified dc power supply, and is configured according to the actual situation of the construction site.
Alternatively, the positive pole of the power supply 1 is connected to the anode plate 5 and the negative pole of the power supply 1 is connected to the perforated cathode plate 2.
Alternatively, the anode plate 5 is an iron or aluminum plate, the perforated cathode plate 2 is a perforated iron or aluminum plate, and the perforated cathode plate 2 and the flat ceramic membrane 3 together form a cathode membrane
Alternatively, the perforated cathode plates 2 and anode plates 5 are arranged in an array.
Optionally, a vacuum water collecting device 6 is connected to the flat ceramic membrane 3 through a vacuum pump and a pipeline for collecting the clarified filtrate.
Optionally, a back-flushing device 7 is connected to the lower end of the flat ceramic membrane 3 through a pipe for back-flushing it with fresh water or high-pressure air.
Optionally, a cone-shaped solid storage slot 9 is detachably mounted below the anode plate 5.
Alternatively, the flat ceramic membrane 3, the perforated cathode plate 2 and the anode plate 5 are all arranged upright at the bottom of the slurry storage tank 4.
Optionally, a horizontal-tank type purge aeration device 8 is arranged at the bottom of the slurry storage tank 4 to generate high-pressure shear gas flow for purging along the cut surfaces of the perforated cathode plate 2 and anode plate 5.
Optionally, more than two groups of the flat ceramic membrane 3, the perforated cathode plate 2 and the anode plate are respectively matched with each other.
Optionally, the vacuum water collecting device 6 comprises a vacuum water collecting tank and a vacuum pump which are communicated with the flat ceramic membrane 3 through a pipeline, and the vacuum water collecting tank and the vacuum pump penetrate through the cathode plate 2 with holes to flow into the flat ceramic membrane 3 and finally converge into the vacuum water collecting tank.
Optionally, high-pressure shearing airflow, namely the blowing aeration 8, is introduced to the bottom of the slurry storage tank 4 along the wall of the tank, so that the slurry is stirred to roll, and the pollution of the flat ceramic membrane and the electrode plate is prevented.
The vacuum water collecting device 6 is connected with the bottom of the flat ceramic membrane 3 through a pipeline, and clear filtrate is collected by utilizing negative pressure generated by vacuumizing. The anode plate 5 gathers soil particles in the electrolytic process, and a solid object storage conical clamping groove 9 for detachably storing the soil particles is arranged at the bottom of the anode plate, so that the soil particles can be periodically removed.
When the equipment starts to operate, the power supply 1 is switched on, an electric field is formed between the cathode plate 2 with holes and the anode plate 5, capillary water and free water in slurry can flow to the cathode plate 2 with holes under the action of the electric field, and slurry particles and soil particles are gathered on the anode plate 5. The negative plate 2 with holes is a plate with holes, clarified filtrate gathered near the cathode is started, a vacuum pump is started to enable the inner cavity of the flat ceramic membrane 3 to generate negative pressure, and the clarified filtrate close to the flat ceramic membrane group 3 enters the vacuum water collecting device 6 along the ceramic membrane holes under the filter pressing effect. The soil particles can be periodically cleaned, treated, maintained and the like through the disassembly of the conical clamping groove 9 for storing the solid matters.
The bottom of the slurry storage tank 4 is provided with a horizontal-tank type purging and aerating device 8, so that high-pressure shearing airflow can be purged along the tangent planes of the porous cathode plate 2 and the porous anode plate 5, slurry is stirred to roll, and the flat ceramic membrane 3, the porous cathode plate 2 and the porous anode plate 5 are prevented from being polluted. The purging and aerating device 8 is arranged below the flat ceramic membrane 3, the porous cathode plate 2 and the porous anode plate 5.
And (3) starting the backwashing device 7 from time to time, and periodically backwashing the flat ceramic membrane group 3 by using clean water or high-pressure airflow to prevent slurry from polluting or blocking the ceramic membrane. And continuously starting the purging aeration device 8, purging the high-pressure shearing airflow along the tangent plane of the porous cathode plate 2, the porous anode plate 5 and the porous ceramic membrane 3, stirring slurry to roll, and preventing the pollution of the porous cathode plate 2, the porous anode plate 5 and the porous ceramic membrane 3. The dry sludge can be removed by a slurry pump through the conical clamping groove 9 for sucking and storing the solid matters, and the dry sludge can be periodically cleaned, treated, maintained and the like.
The working principle of the invention is as follows: under the action of an external direct current electric field, free water and bound water in the slurry are densely gathered on the surface of the slurry under the influence of the electric field force; the slurry particles are negatively charged, and the free water and the bound water are positively charged; the two charges respectively move towards the anode plate and the cathode plate with holes in a directional manner; water molecules pass through the cathode plate membrane, so that mud and water are separated, mud particles are concentrated at the anode plate, and mud dehydration is realized.
The anode and cathode of the electrode are both hollow aluminum or iron plates with holes, and after direct current is introduced and a direct current generator or a direct current welding machine is adopted, soil particles with negative charges move to the anode plate, namely electrophoresis is performed, and water with positive charges is concentrated to the cathode plate with holes, so that an electroosmosis phenomenon is generated. Under the double action of electroosmosis and vacuum in the porous hollow plate, water in the clay is forced to be rapidly discharged from the porous hollow plate, and the porous hollow plate continuously pumps water, so that the dehydration of the slurry is realized.
The above embodiments are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical solution according to the technical idea of the present invention can be implemented by the prior art.
Claims (10)
1. The utility model provides a shield constructs mud dewatering device which characterized in that: the device comprises a power supply (1), a negative plate (2) with holes connected with the power supply (1), a flat ceramic membrane (3) adjacent to the negative plate (2) with the holes, a slurry storage tank (4), an anode plate (5), a vacuum water collecting device (6), a back washing device (7), a purging aeration device (8) and a conical clamping groove (9) for storing solid matters, wherein the negative plate with holes (2) is connected with the negative pole of the power supply (1), and the anode plate (5) is connected with the positive pole of the power supply (1); the flat ceramic membrane (3) and the negative plate (2) with holes form a cathode membrane together, the upper end of the flat ceramic membrane (3) is connected with a vacuum water collecting device (6), the vacuum water collecting device (6) is used for collecting collected electrolytic clarified filtrate flowing from the negative plate (2) with holes and the flat ceramic membrane (3) during dehydration operation, and the lower end of the flat ceramic membrane (3) is connected with a backwashing device (7) which is used for backwashing the flat ceramic membrane (3) to prevent soil particle blockage; the bottom of the slurry storage tank (4) is provided with a solid storage conical clamping groove (9) and a purging and aerating device (8), the solid storage conical clamping groove (9) is used for collecting positive ion soil particles stored near the anode plate (5) during dewatering operation, and the purging and aerating device (8) is used for blowing high-pressure gas to stir slurry to roll.
2. The shield mud dewatering device of claim 1, wherein: the positive pole of the power supply (1) is connected with the anode plate (5), and the negative pole of the power supply (1) is connected with the cathode plate (2) with holes.
3. The shield mud dewatering device of claim 1, wherein: the anode plate (5) is an iron or aluminum plate, the cathode plate (2) with holes is an iron or aluminum plate with holes, and the cathode plate (2) with holes and the flat ceramic membrane (3) form a cathode membrane together.
4. The shield mud dewatering device of claim 1, wherein: the perforated cathode plates (2) and the perforated anode plates (5) are arranged in an array.
5. The shield mud dewatering device of claim 1, wherein: the vacuum water collecting device (6) is connected with the flat ceramic membrane (3) through a vacuum pump and a pipeline and is used for collecting clear filtrate.
6. The shield mud dewatering device of claim 1, wherein: the back washing device (7) is connected with the lower end of the flat ceramic membrane (3) through a pipeline and is used for back washing the flat ceramic membrane by adopting clean water or high-pressure airflow.
7. The shield mud dewatering device of claim 1, wherein: the conical clamping groove (9) for storing the solid objects is detachably arranged below the anode plate (5).
8. The shield mud dewatering device of claim 1, wherein: the flat ceramic membrane (3), the perforated cathode plate (2) and the anode plate (5) are all vertically arranged at the bottom of the slurry storage tank (4).
9. The shield mud dewatering device of claim 1, wherein: a horizontal-groove type purging and aerating device (8) is arranged at the bottom of the slurry storage tank (4) and used for generating high-pressure shearing airflow for purging on the tangent planes of the cathode plate (2) and the anode plate (5) with holes.
10. The shield mud dewatering apparatus of any one of claims 1-9, wherein: more than two groups of flat ceramic membranes (3), the negative plates (2) with holes and the positive plates are respectively matched with each other.
Priority Applications (1)
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CN201921104618.7U CN211035588U (en) | 2019-07-15 | 2019-07-15 | Shield mud dewatering device |
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CN201921104618.7U CN211035588U (en) | 2019-07-15 | 2019-07-15 | Shield mud dewatering device |
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CN211035588U true CN211035588U (en) | 2020-07-17 |
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CN201921104618.7U Expired - Fee Related CN211035588U (en) | 2019-07-15 | 2019-07-15 | Shield mud dewatering device |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110422956A (en) * | 2019-07-15 | 2019-11-08 | 湖南大学 | A kind of shield slurry dehydration device |
CN113463164A (en) * | 2021-06-30 | 2021-10-01 | 南京林业大学 | Electrophoresis system and method for improving shield engineering mud film strength and air-tightness |
CN113603335A (en) * | 2021-06-16 | 2021-11-05 | 郑州大学 | Vacuum-electroosmosis dewatering device for shield waste mud |
-
2019
- 2019-07-15 CN CN201921104618.7U patent/CN211035588U/en not_active Expired - Fee Related
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN110422956A (en) * | 2019-07-15 | 2019-11-08 | 湖南大学 | A kind of shield slurry dehydration device |
CN113603335A (en) * | 2021-06-16 | 2021-11-05 | 郑州大学 | Vacuum-electroosmosis dewatering device for shield waste mud |
CN113463164A (en) * | 2021-06-30 | 2021-10-01 | 南京林业大学 | Electrophoresis system and method for improving shield engineering mud film strength and air-tightness |
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Granted publication date: 20200717 Termination date: 20210715 |