CN114470892A - Hydraulic spiral-flow type backwashing filter device and method - Google Patents
Hydraulic spiral-flow type backwashing filter device and method Download PDFInfo
- Publication number
- CN114470892A CN114470892A CN202210031144.8A CN202210031144A CN114470892A CN 114470892 A CN114470892 A CN 114470892A CN 202210031144 A CN202210031144 A CN 202210031144A CN 114470892 A CN114470892 A CN 114470892A
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- filtering
- water
- pipe
- main body
- back washing
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D24/00—Filters comprising loose filtering material, i.e. filtering material without any binder between the individual particles or fibres thereof
- B01D24/46—Regenerating the filtering material in the filter
- B01D24/4631—Counter-current flushing, e.g. by air
- B01D24/4636—Counter-current flushing, e.g. by air with backwash shoes; with nozzles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D24/00—Filters comprising loose filtering material, i.e. filtering material without any binder between the individual particles or fibres thereof
- B01D24/46—Regenerating the filtering material in the filter
- B01D24/4626—Construction of spray heads specially adapted for regeneration of the filter material or for filtrate discharging
Abstract
The invention provides a hydraulic spiral-flow type backwashing filter device and a method, which comprise a filter main body and a backwashing component, wherein the filter main body is of a cylindrical barrel structure, a filter material is filled in the filter main body, the top opening is a sewage inlet, the top side wall is connected with a backwashing sewage pipe, the bottom of the filter main body is connected with a water collecting pipe, the bottom of the water collecting pipe is connected with a filtering clean water pipe, a water filtering plate is arranged at the joint of the filter main body and the water collecting pipe, water filtering holes are distributed on the water filtering plate, and a filter cap is correspondingly arranged on the water filtering plate; the back washing component comprises a plurality of rotational flow back washing water pipes and a vertical back washing water pipe, wherein the rotational flow back washing water pipes are uniformly arranged at intervals along the circumferential surface of the lower part of the filtering main body, the rotational flow back washing water pipes are tangent to the outer edge of the filtering main body in the radial direction, and the vertical back washing water pipe is arranged on the side wall of the water collecting pipe.
Description
Technical Field
The invention belongs to the technical field of sewage filtration and purification, and particularly relates to a hydraulic spiral-flow type backwashing filter device and method.
Background
A filtering device for filtering river sewage in a waterworks mainly utilizes quartz sand as a filtering material, and the principle of the filtering device is that suspended matters, organic matters and impurity particles in the sewage are filtered by utilizing the interception effect among gaps of the quartz sand to obtain filtered clear water. Along with filtering sewage of a period of time, produce a large amount of impurity between the quartz sand space and blockked up the space, the great reduction of filter effect for need carry out the back flush effect after filter equipment work a period, adopt rivers from bottom to top promptly, expand the filter material and wash, wash away the impurity that the filter material was held back, make the filter material resume filter effect.
However, although the impurity particles can be separated out by the water flow from bottom to top, the larger impurities can still float on the upper surface of the filter material and cannot be washed out along with the water flow, so that the subsequent filtering effect of the filter material is affected, the water consumption of the back washing filter material is large, and the filter material cannot be cleaned completely and effectively.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a hydraulic spiral-flow type backwashing filter device and method aiming at the existing problems, and the adopted spiral-flow principle greatly improves the backwashing efficiency.
The technical scheme adopted by the invention for solving the technical problems is as follows: a hydraulic spiral-flow type backwashing filter device is characterized by comprising a filter main body and a backwashing component, wherein the filter main body is of a cylindrical barrel structure, a filter material is filled in the filter main body, the top opening is a sewage inlet, the top side wall is connected with a backwashing sewage pipe, the bottom of the filter main body is connected with a water collecting pipe, the bottom of the water collecting pipe is connected with a filtering clean water pipe, a water filtering plate is arranged at the joint of the filter main body and the water collecting pipe, water filtering holes are distributed in the water filtering plate, and a filter cap is correspondingly arranged in the water filtering holes; the back washing assembly comprises a plurality of rotational flow back washing water pipes and a plurality of vertical back washing water pipes, the rotational flow back washing water pipes are uniformly arranged along the circumferential surface of the lower part of the filtering main body at intervals, the rotational flow back washing water pipes are tangent to the outer edge of the filtering main body in the radial direction, and the vertical back washing water pipes are arranged on the side wall of the water collecting pipe.
According to the scheme, the upper part of the filtering main body is provided with the water collecting tank, the water collecting tank is of a cylindrical tank structure with an opening at the top and a connecting hole at the center of the bottom plate, the aperture of the connecting hole is the same as the outer diameter of the filtering main body, the water collecting tank is sleeved outside the filtering main body and is fixedly connected with the outer wall of the filtering main body, and the backwashing sewage pipe is communicated with the outer wall of the water collecting tank.
According to the scheme, the rotational flow back washing water pipe, the vertical back washing water pipe and the filtering clean water pipe are all provided with one-way valves.
According to the scheme, the water collecting pipe is of a conical barrel structure, the diameter of a large opening is the same as that of the filtering main body, and the diameter of a small opening is the same as that of the filtering clean water pipe.
According to the scheme, the height of the top opening of the water collecting tank is larger than that of the top opening of the filtering main body, and the pipe opening of the backwashing sewage pipe is flush with the bottom plate of the water collecting tank.
A hydraulic cyclone type backwashing filtering method is characterized by comprising the following steps:
s1) sewage filtration: sewage to be filtered enters the filtering main body from the sewage inlet, impurity particles and suspended matters in the sewage are intercepted in the filtering material layer through the interception effect of the filtering material, and finally filtered clear water is discharged from the filtering clear water pipe to obtain filtered clear water;
s2) backwashing: closing the one-way valve of the filtering clean water pipe, opening the one-way valves of the rotational flow back washing water pipe and the vertical back washing water pipe, making the tap water flow into the filtering main body from the rotational flow back washing water pipe and the vertical back washing water pipe, performing rotational flow expansion on the filtering materials, washing off impurity particles attached to the surface of the filtering materials and gaps among the filtering materials by utilizing collision among the filtering materials, and discharging the impurity particles floating on the upper layer of the filtering materials from the back washing sewage pipe by utilizing the rotational flow effect.
The invention has the beneficial effects that: the periphery of the filter main body is added with a plurality of backwashing water pipes in the tangential direction, the direction of the backwashing water flow which is vertically upward is changed into the direction of the water flow which flows upward in the subsequent tangential direction around the cylinder, the interaction between filter materials can be stronger by utilizing the rotational flow effect, the friction between the filter materials is enhanced, the impurity particles between the filter materials can be more effectively cleaned, and the cleaning efficiency is improved; meanwhile, the impurity particles in the middle can be better discharged out of the filtering device by utilizing the rotational flow effect, so that a better cleaning effect is achieved.
Drawings
Fig. 1 is a schematic structural diagram of an embodiment of the present invention.
FIG. 2 is a graph showing the effect of turbidity of water after backwashing in different directions of backwashing water flow according to an embodiment of the present invention.
Detailed Description
For a better understanding of the present invention, reference is made to the following description taken in conjunction with the accompanying drawings and examples.
As shown in fig. 1, a hydraulic spiral-flow type backwashing filter device comprises a filter main body 1 and a backwashing assembly, wherein the filter main body is of a cylindrical structure, a filter material is filled in the filter main body, the top opening is a sewage inlet 2, the top side wall is connected with a backwashing sewage pipe 3, the bottom of the filter main body is connected with a water collecting pipe 4, the bottom of the water collecting pipe is connected with a filtering clean water pipe 5, a water filtering plate 6 is arranged at the joint of the filter main body and the water collecting pipe, water filtering holes 7 are distributed on the water filtering plate, and a filter cap is correspondingly arranged on the water filtering holes; the back washing component comprises a plurality of rotational flow back washing water pipes 8 and a vertical back washing water pipe 9, the rotational flow back washing water pipes are uniformly arranged along the circumferential surface of the lower part of the filtering main body at intervals, the rotational flow back washing water pipes are tangent with the outer edge of the filtering main body in the radial direction, and the vertical back washing water pipe is arranged on the side wall of the water collecting pipe.
The upper part of the filtering main body is provided with a water collecting tank 10, the water collecting tank is of a cylindrical tank structure with an opening at the top and a connecting hole at the center of the bottom plate, the aperture of the connecting hole is the same as the outer diameter of the filtering main body, the water collecting tank is sleeved outside the filtering main body and is connected and fastened with the outer wall of the filtering main body, and the backwashing sewage pipe is communicated with the outer wall of the water collecting tank.
Check valves are arranged on the rotational flow back washing water pipe, the vertical back washing water pipe and the filtering clean water pipe, and the on-off of the pipelines is controlled by the on-off of the check valves.
The water collecting pipe is in a conical cylinder structure, the diameter of a large opening is the same as that of the filtering main body, and the diameter of a small opening is the same as that of the filtering clean water pipe. Through setting up the collector pipe, can the great filter of area be installed to can set up a plurality of filter caps on it, increase filtration efficiency.
According to the scheme, the height of the top opening of the water collecting tank is larger than that of the top opening of the filtering main body, and the pipe opening of the backwashing sewage pipe is flush with the bottom plate of the water collecting tank.
The method for filtering sewage by adopting the hydraulic spiral-flow type backwashing filter device comprises the following steps:
(1) filtering sewage: sewage to be filtered enters the filtering main body from the sewage inlet, impurity particles and suspended matters in the sewage are intercepted in the filtering material layer through the intercepting function of the filtering material, and finally filtered clean water is discharged from the filtering clean water pipe to obtain filtered clean water.
(2) Backwashing: closing a one-way valve of the clean water filtering pipe, opening a one-way valve of the rotational flow back-flushing water pipe and the vertical back-flushing water pipe, enabling tap water flow to flow into the filtering main body from the rotational flow back-flushing water pipe and the vertical back-flushing water pipe, performing rotational flow expansion on the filtering materials, flushing impurity particles attached to the surfaces of the filtering materials and gaps among the filtering materials by utilizing collision among the filtering materials, and discharging the impurity particles floating on the upper layer of the filtering materials from the back-flushing sewage pipe by utilizing the rotational flow effect.
Example one
The diameter of a sewage inlet of the filtering main body is 250mm, the length of the sewage inlet is 1500mm, the pipe diameter of a transverse backwashing sewage pipe above the filtering main body is 200mm, the diameter of a filtering clean water pipe is 75mm, a layer of partition plate is arranged below the filtering main body, and seven filtering caps are arranged in the middle of the partition plate.
After the same filtering experiment is carried out on the filtering device, a comparison graph (shown in figure 2) of the water turbidity effect after backwashing in different backwashing water flow directions (vertical backwashing water flow and rotational flow backwashing water flow) is shown, the backwashing effect of the rotational flow water flow is found to be obviously better than that of the vertical water flow, the rotational flow water flow can reach the water turbidity of 1NTU after backwashing for five minutes, and the vertical water flow can reach the water turbidity of 1NTU after fifteen minutes, so that the backwashing efficiency is greatly improved.
While the present invention has been described with reference to the particular embodiments illustrated in the drawings, which are meant to be illustrative only and not limiting, it will be apparent to those of ordinary skill in the art in light of the teachings of the present invention that numerous modifications can be made without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (6)
1. A hydraulic spiral-flow type backwashing filter device is characterized by comprising a filter main body and a backwashing component, wherein the filter main body is of a cylindrical barrel structure, a filter material is filled in the filter main body, the top opening is a sewage inlet, the top side wall is connected with a backwashing sewage pipe, the bottom of the filter main body is connected with a water collecting pipe, the bottom of the water collecting pipe is connected with a filtering clean water pipe, a water filtering plate is arranged at the joint of the filter main body and the water collecting pipe, water filtering holes are distributed in the water filtering plate, and a filter cap is correspondingly arranged in the water filtering holes; the back washing assembly comprises a plurality of rotational flow back washing water pipes and a plurality of vertical back washing water pipes, the rotational flow back washing water pipes are uniformly arranged along the circumferential surface of the lower part of the filtering main body at intervals, the rotational flow back washing water pipes are tangent to the outer edge of the filtering main body in the radial direction, and the vertical back washing water pipes are arranged on the side wall of the water collecting pipe.
2. The air water collecting device of claim 1, wherein the filtering body is provided with a water collecting tank at an upper portion thereof, the water collecting tank is a cylindrical tank structure having an open top and a connecting hole at a center of the bottom plate, the connecting hole has a diameter equal to an outer diameter of the filtering body, the water collecting tank is sleeved on the filtering body and is fastened to an outer wall of the filtering body, and the backwashing sewer pipe is communicated with the outer wall of the water collecting tank.
3. An air water collecting device according to claim 2, wherein the cyclone back-flushing water pipe, the vertical back-flushing water pipe and the filtered clean water pipe are provided with one-way valves.
4. An air water collecting device according to claim 1, 2 or 3, wherein said water collecting pipe is a conical cylinder structure, the diameter of the large mouth is the same as the diameter of said filtering main body, and the diameter of the small mouth is the same as the diameter of said filtering clean water pipe.
5. An air collection unit according to claim 2 or 3, wherein the height of the top opening of the water collection sump is greater than the height of the top opening of the filter body, and the mouth of the backwash sewage pipe is flush with the floor of the water collection sump.
6. A hydraulic cyclone type backwashing filtering method is characterized by comprising the following steps:
s1) sewage filtration: sewage to be filtered enters the filtering main body from the sewage inlet, impurity particles and suspended matters in the sewage are intercepted in the filtering material layer through the interception effect of the filtering material, and finally filtered clear water is discharged from the filtering clear water pipe to obtain filtered clear water;
s2) backwashing: closing the one-way valve of the filtering clean water pipe, opening the one-way valves of the rotational flow back washing water pipe and the vertical back washing water pipe, making the tap water flow into the filtering main body from the rotational flow back washing water pipe and the vertical back washing water pipe, performing rotational flow expansion on the filtering materials, washing off impurity particles attached to the surface of the filtering materials and gaps among the filtering materials by utilizing collision among the filtering materials, and discharging the impurity particles floating on the upper layer of the filtering materials from the back washing sewage pipe by utilizing the rotational flow effect.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210031144.8A CN114470892A (en) | 2022-01-12 | 2022-01-12 | Hydraulic spiral-flow type backwashing filter device and method |
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| CN202210031144.8A CN114470892A (en) | 2022-01-12 | 2022-01-12 | Hydraulic spiral-flow type backwashing filter device and method |
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| CN114470892A true CN114470892A (en) | 2022-05-13 |
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| CN202210031144.8A Pending CN114470892A (en) | 2022-01-12 | 2022-01-12 | Hydraulic spiral-flow type backwashing filter device and method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116835711A (en) * | 2023-07-26 | 2023-10-03 | 戴思乐科技集团有限公司 | Backwashing method and filtering equipment of leisure water body filtering device |
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2022
- 2022-01-12 CN CN202210031144.8A patent/CN114470892A/en active Pending
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