CN112062284A - Sewage plant tail water treatment system - Google Patents
Sewage plant tail water treatment system Download PDFInfo
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- CN112062284A CN112062284A CN202010938265.1A CN202010938265A CN112062284A CN 112062284 A CN112062284 A CN 112062284A CN 202010938265 A CN202010938265 A CN 202010938265A CN 112062284 A CN112062284 A CN 112062284A
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- water
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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
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/32—Biological treatment of water, waste water, or sewage characterised by the animals or plants used, e.g. algae
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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
- C02F2301/00—General aspects of water treatment
- C02F2301/08—Multistage treatments, e.g. repetition of the same process step under different conditions
Abstract
The invention belongs to the technical field of biological treatment of sewage by using plants as characteristics, and particularly relates to a tail water treatment system of a sewage plant. The treatment system comprises a water inlet and a water outlet, the water inlet and the water outlet are communicated through a hairpin-shaped bent ditch, a substrate is laid at the bottom of the hairpin-shaped bent ditch, submerged plants are planted on the substrate, a plurality of groups of regulating plate sets are sequentially arranged in the hairpin-shaped bent ditch between the water inlet and the water outlet, each group of regulating plate set comprises a first-class water flow regulating plate and a second-class water flow regulating plate, the first-class water flow regulating plate is arranged at the bottom of the hairpin-shaped bent ditch, the top of the first-class water flow regulating plate is lower than the water surface, the second-class water flow regulating plate is arranged; the first-class water flow adjusting plate and the second-class water flow adjusting plate are sequentially arranged at intervals. The system has good effect of removing nitrogen and phosphorus in the tail water of the sewage plant.
Description
Technical Field
The invention belongs to the technical field of biological treatment of sewage by using plants as characteristics, and particularly relates to a tail water treatment system of a sewage plant.
Background
With the continuous promotion of the urbanization process and the improvement of the living standard of people, a large number of people are rushed into cities, and the scale of towns is continuously enlarged. However, as towns are scaled up, environmental pressures caused by population problems are increasing (research on problems and countermeasures for water and soil conservation in cities, songbei, black longjiang water conservancy science, vol.46, No. 7 in 2018, pages 279, abstract lines 1-2, publication days 2018, 12 and 31), such as increasing urban sewage production.
At present, most of tail water of sewage treatment plants in China is directly discharged into nearby natural receiving water bodies such as rivers, lakes and the like through surface runoff. Although most of the tail water of the urban sewage treatment plants can reach the first-class A or first-class B discharge standard of the GB 18918-2002 pollutant discharge standard of the urban sewage treatment plants, the tail water can not reach the V-class water quality standard of the GB 3838-2002 quality standard of surface water environment, for example, the chemical oxygen demand COD in the first-class A discharge standard is 50 mg.L-1Total nitrogen 15 mg.L-1Total phosphorus is 1 mg.L-1And the chemical oxygen demand COD in the V-class water quality standard is 40 mg.L-1Total nitrogen of 2 mg. L-1Total phosphorus of 0.4 mg. L-1. That is, the total phosphorus content of the I-type water on the earth surface of more than 1.5 tons or the total nitrogen content of the I-type water on the earth surface of more than 7.2 tons of the tail water discharged by reaching the first-grade A standard can reach the V-type water. Although the water quality of most natural water bodies in China is far higher than the V-type water standard, the tail water of urban sewage treatment plants after treating billions of tons of domestic sewage every day is still a potential pollution source of natural water environment.
In order to reduce the pollution of the tail water discharged by the sewage treatment plant to the surface water, the tail water can be deeply treated before being discharged into the receiving water body so as to reduce or intercept the pollutants of nitrogen, phosphorus and the like in the tail water. Physical, chemical and biological methods such as activated carbon adsorption, coagulation, precipitation, biomembrane and the like are commonly adopted for advanced treatment of tail water, but the methods have the defects of high investment and operation cost, secondary pollution, non-ideal purification effect and the like in the application process, thereby limiting the wide application of the methods.
For example, patent document with publication number CN110217891A discloses a process for removing nitrogen from tail water of sewage treatment plants by using an artificial wetland, in which a vertical subsurface flow wetland and a surface flow wetland are combined in series, the ammonia nitrogen content (1.5mg/L) after treatment reaches the standard of surface water class iv, but the total nitrogen content (less than or equal to 2.13mg/L) cannot reach the standard, and there is no obvious effect of removing total phosphorus. Patent document No. CN111268804ADiscloses a method for removing pollutants in tail water of a sewage plant by utilizing a wetland system, wherein the wetland system comprises an enhanced facultative wetland, a biological purification wetland and a submerged plant wetland. However, the wetland system needs additional carbon source, the ventilation of the fan increases the investment of dissolved oxygen and the like, each treatment unit has complicated construction engineering, higher operation cost and technical requirements, and smaller water treatment capacity (6 m)3H), in addition, the system has low removal rate of total nitrogen, which is only about 42.9%.
Disclosure of Invention
In view of the above, the present invention provides a sewage treatment system for sewage plants.
In order to achieve the purpose, the technical scheme of the invention is as follows:
the sewage tail water treatment system comprises a water inlet and a water outlet, wherein the water inlet and the water outlet are communicated through a hairpin-shaped bent ditch, a substrate is laid at the bottom of the hairpin-shaped bent ditch, submerged plants are planted on the substrate, a plurality of groups of regulating plate sets are sequentially arranged in the hairpin-shaped bent ditch between the water inlet and the water outlet, each water flow regulating plate set comprises a first-class water flow regulating plate and a second-class water flow regulating plate, the first-class water flow regulating plate is arranged at the bottom of the hairpin-shaped bent ditch, the top of the first-class water flow regulating plate is lower than the water surface, and the front plate of the second-class water flow regulating plate; the first-class water flow adjusting plate and the second-class water flow adjusting plate are sequentially arranged at intervals.
Further, the wall of the hairpin-shaped curved ditch comprises a stone, pebble or brick-concrete structure.
Furthermore, the width of the hairpin bending ditch is 0.4-1.2m, and the depth of the ditch is not less than 1.2 m.
Further, the submerged plant includes 1-3 kinds of dwarf evergreen picrasma, hydrilla verticillata and curly pondweed.
Furthermore, the plant spacing of the submerged plants is 15-20cm, and the row spacing is 20-30 cm.
Further, the matrix comprises a mixture of purple parent rock and dolomite or limestone.
Further, the particle size of the purple mother rock is 20-40 mm.
Furthermore, the particle size of the dolomite or limestone is 20-40 mm.
Further, the thickness of the substrate is 20-40 cm.
Furthermore, the water flow adjusting plates adopt cement precast slabs, stone slabs or brick-concrete structures.
Furthermore, the second type of water flow adjusting plate adopts a cement precast slab, a stone slab or a brick-concrete structure.
Furthermore, the interval between the water flow adjusting plate groups consisting of the first-class water flow adjusting plate and the second-class water flow adjusting plate is 10-20 m.
The invention also aims to protect the sewage tail water treatment method of the sewage plant, which adopts the system for treatment.
The invention has the beneficial effects that:
the system has good effect of removing nitrogen and phosphorus in the tail water of the sewage plant, the treated tail water can reach COD and ammonia nitrogen which reach the II-class water standard of the earth surface, and TN and TP can reach the V-class water quality standard of the earth surface for stable discharge.
The system of the invention has large water treatment capacity.
The system of the invention is environment-friendly, has no energy consumption and no external carbon source.
The system of the invention has simple structure and low construction and operation cost.
Drawings
Fig. 1 is a schematic plan view of a tail water treatment system of a sewage plant of example 1, in which 1 is a water inlet, 3 is a trench wall, 4 is a water flow, 5 is a submerged plant, and 6 is a water outlet;
fig. 2 is a schematic sectional view of the tail water treatment system of the sewage plant of example 1, in which 4 is water flow, 5 is submerged plants, 21 is one type of flow regulating plate, 22 is a second type of flow regulating plate, and 7 is a substrate.
Detailed Description
The examples are provided for better illustration of the present invention, but the present invention is not limited to the examples. Therefore, those skilled in the art should make insubstantial modifications and adaptations to the embodiments of the present invention in light of the above teachings and remain within the scope of the invention.
The following ammonia nitrogen content is detected according to salicylic acid-hypochlorite spectrophotometry (A) for detecting the ammonia nitrogen content in the twelfth part of the third chapter of the Water and wastewater monitoring and analyzing method (the fourth edition of the supplement);
detecting the chemical oxygen demand COD according to a rapid digestion spectrophotometry for measuring the chemical oxygen demand of the HJ/T399-;
detecting the following total nitrogen content according to GB/T11894-1989 alkaline potassium persulfate digestion ultraviolet spectrophotometry for measuring total nitrogen in water;
the following total phosphorus content was measured according to GB/T11893-1989 ammonium molybdate spectrophotometry for measuring total phosphorus in water.
Example 1
As shown in fig. 1 and fig. 2, in the tail water treatment system of a sewage plant, the periphery of a river beach near the site of a certain sewage plant is built by gravels after digging and leveling, a 24-wall with the height of 1.2m is built by red bricks in the middle, concrete powder is used for coating and preventing seepage, a four-turning five-grid hairpin bent ditch is built, the width of the ditch is 1.2m, the total length exceeds 1200m, and the ditch is provided with a water inlet 1 and a water outlet 6;
a substrate 7 is laid at the bottom of the hairpin curved ditch, submerged plants 5 are planted on the substrate 7, a plurality of groups of regulating plate groups are sequentially arranged in the hairpin curved ditch between the water inlet 1 and the water outlet 6, each water flow regulating plate group comprises a first-class water flow regulating plate 21 and a second-class water flow regulating plate 22, a front plate of the first-class water flow regulating plate 21 is arranged at the bottom of the hairpin curved ditch, the top of the first-class water flow regulating plate is lower than the water surface, a rear plate of the first-class water flow regulating plate 21 is arranged above the substrate, the top of the rear plate is higher than the water surface, a front plate of the second-class water flow regulating plate 22 is arranged above the substrate, the top of;
the first-class water flow adjusting plate 21 and the second-class water flow adjusting plate 22 are sequentially arranged at intervals, specifically, the first-class water flow adjusting plate 21 and the second-class water flow adjusting plate 22 are sequentially arranged, the distance between the first-class water flow adjusting plate 21 and the second-class water flow adjusting plate 22 is 20-40cm, the first-class water flow adjusting plate 21 is arranged at an interval of 10-20m, the second-class water flow adjusting plate 22 and the first-class water flow adjusting plate 21 are sequentially arranged at an interval of 10-20m, the distance between the two plates is 20-40cm, and the second-class water flow adjusting plate is arranged at an interval of 10-20 m;
specifically, two ends of a first-class water flow adjusting plate 21 are connected with the channel wall 3 of the hairpin bending ditch, the bottom end of the plate is positioned at a position 10-20cm above the substrate 7, and the top end of the plate exceeds the operating water level by 10-20 cm;
specifically, two ends of the second-class water flow adjusting plate 22 are connected with the channel wall 3 of the hairpin curved ditch, the bottom end of the second-class water flow adjusting plate is connected with the bottom of the hairpin curved ditch, and the top end of the second-class water flow adjusting plate is 10-20cm lower than the operating water level;
mixing limestone (with the particle size of 20-40mm) and purple mother rock (with the particle size of 20-40mm) according to the mass ratio of 1:2, filling the mixture into the bottom of a ditch to serve as a matrix 7, wherein the thickness of the matrix 7 is 35 cm;
introducing stream water into the ditch until the water depth is 30cm, planting hydrilla verticillata on the substrate 7 of the first half section of the ditch according to the plant spacing of 20cm and the row spacing of 20cm, and planting dwarf evergreen tape grass on the substrate of the second half section of the ditch according to the plant spacing of 15cm and the row spacing of 20 cm;
in this embodiment, specifically, the first-class water flow regulating plate 21 and the second-class water flow regulating plate 22 are brick-concrete 12 wall structures;
and gradually introducing tail water to the water depth of 80cm along with the growth of submerged plants, and starting to put into operation.
When the system is used for treating tail water of a sewage plant, the tail water of the sewage plant is introduced from the water inlet 1, and the flow rate is 60m3And h, keeping the running water depth at about 80cm, and channeling to the water outlet 6 (after treatment) through the hairpin bend water.
Performance detection
The ammonia nitrogen content, Chemical Oxygen Demand (COD), total nitrogen content and total phosphorus content in the wastewater from the sewage plant before and after treatment in example 1 were measured, and the results are shown in Table 1.
TABLE 1 test results
| Origin of origin | Content of ammonia nitrogen/(mg/L) | Chemical oxygen demand COD/(mg/L) | Total nitrogen content/(mg/L) | Total phosphorus content/(mg/L) |
| Example 1 Prior to treatment | 1.64 | 43.68 | 12.24 | 1.34 |
| Example 1 after treatment | 0.48 | 12.43 | 1.67 | 0.32 |
As can be seen from Table 1, the ammonia nitrogen content of the tail water of the sewage plant is reduced to 0.48mg/L, the chemical oxygen demand COD is reduced to 12.43mg/L, the total nitrogen content is reduced to 1.67mg/L, and the total phosphorus content is reduced to 0.32mg/L after the treatment of the example 1. Therefore, the system has good nitrogen and phosphorus treatment effect on the tail water of the sewage plant, the treated tail water can reach COD and ammonia nitrogen which reach the II-class water standard of the earth surface, and TN and TP reach the V-class water quality standard of the earth surface for stable discharge.
Example 2
When a rural movable square is built in a certain place, a landscape pond is reformed, and meanwhile, a local polluted natural water body and a small amount of sewage tail water of a rural food factory are treated and then introduced into a landscape water body;
this embodiment is substantially the same as embodiment 1, except that: constructing 24 walls with the height of 1.2m on the landscape pond part by red bricks, applying concrete powder for seepage prevention, constructing a four-lattice hairpin bent ditch with three-turn directions, the width of the ditch is 1.2m, the total length is over 400m,
the specific construction and operation process is the same as that of the embodiment 1, and the differences are as follows: the water flow is 10m3H (wherein the tail water of the sewage of the food factory is 2m3/h)。
Performance detection
The ammonia nitrogen content, Chemical Oxygen Demand (COD), total nitrogen content and total phosphorus content in the wastewater from the sewage plant before and after treatment in example 2 were measured, and the results are shown in Table 2.
TABLE 2 test results
| Origin of origin | Content of ammonia nitrogen/(mg/L) | Chemical oxygen demand COD/(mg/L) | Total nitrogen content/(mg/L) | Total phosphorus content/(mg/L) |
| Example 2 Prior to treatment | 1.04 | 23.55 | 2.17 | 1.12 |
| Example 2 after treatment | 0.36 | 8.24 | 1.53 | 0.28 |
As can be seen from Table 2, the ammonia nitrogen content of the polluted natural water body treated by the method of example 2 is reduced to 0.36mg/L, the Chemical Oxygen Demand (COD) is reduced to 8.24mg/L, the total nitrogen content is reduced to 1.53mg/L, and the total phosphorus content is reduced to 0.28 mg/L. Therefore, the system has good nitrogen and phosphorus treatment effect on the naturally polluted water body, the treated tail water can reach COD and ammonia nitrogen to reach the II-class water standard on the earth surface, and TN and TP can reach the V-class water quality standard on the earth surface for stable discharge.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (10)
1. The tail water treatment system of the sewage plant comprises a water inlet and a water outlet and is characterized in that,
the water inlet and the water outlet are communicated through a hairpin-shaped bent ditch, a substrate is laid at the bottom of the hairpin-shaped bent ditch, submerged plants are planted on the substrate, a plurality of groups of regulating plate sets are sequentially arranged in the hairpin-shaped bent ditch between the water inlet and the water outlet, each water flow regulating plate set comprises a first-class water flow regulating plate and a second-class water flow regulating plate, the first-class water flow regulating plate is arranged at the bottom of the hairpin-shaped bent ditch, the top of the first-class water flow regulating plate is lower than the water surface, the second-class water flow regulating plate is arranged above the substrate; the first-class water flow adjusting plate and the second-class water flow adjusting plate are sequentially arranged at intervals.
2. The sewage plant sewage tail water treatment system of claim 1, wherein the trench wall of the hairpin curved trench comprises a stone, pebble, or brick-and-concrete structure.
3. The sewage treatment plant sewage tail water treatment system of claim 1 or 2, wherein the hairpin curved drain has a width of 0.4-1.2m and a depth of more than 1.2 m.
4. The wastewater treatment system of a sewage plant of any of claims 1 to 3, wherein said submerged plants include 1 to 3 species of said aquatic plants selected from the group consisting of said uropatorium fortunei, said nigrospora biflorum and said curly pondweed.
5. The sewage plant tail water treatment system according to any one of claims 1 to 4, wherein the submerged plant has a plant spacing of 15 to 20cm and a row spacing of 20 to 30 cm.
6. The sewage plant tail water treatment system of any of claims 1-5, wherein the substrate comprises a mixture of purple mother rock and dolomite or limestone.
7. The sewage plant tail water treatment system of claim 6, wherein the purple parent rock has a particle size of 20-40 mm.
8. The sewage plant tail water treatment system of claim 7, wherein the substrate has a thickness of 20-40 cm.
9. The sewage plant tail water treatment system of any one of claims 1 to 8, wherein the group of flow regulating plates consisting of the first type flow regulating plate and the second type flow regulating plate is disposed at a distance of 10 to 20 m.
10. A method for treating tail water from a sewage plant, characterized in that the system according to any one of claims 1-9 is used for the treatment.
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| CN202010938265.1A CN112062284A (en) | 2020-09-09 | 2020-09-09 | Sewage plant tail water treatment system |
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| CN202010938265.1A CN112062284A (en) | 2020-09-09 | 2020-09-09 | Sewage plant tail water treatment system |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19630831A1 (en) * | 1996-07-31 | 1998-02-05 | Dernbach Heinrich Gmbh | Multistage biological sewage treatment system |
| CN101314511A (en) * | 2008-04-30 | 2008-12-03 | 华南农业大学 | Baffling type method and system for processing sanitary sewage of horizontal drowned flow artificial wet land |
| CN102190376A (en) * | 2011-05-05 | 2011-09-21 | 西安理工大学 | Integrated flow constructed wetland treatment system |
| CN103819003A (en) * | 2014-02-26 | 2014-05-28 | 桂林理工大学 | Method for treating sewage by utilizing constructed wetland convenient for water sampling |
| CN103951067A (en) * | 2014-04-23 | 2014-07-30 | 广东中大环保科技投资有限公司 | System and method for treating rural sewage by using ecological system based on multi-submerged plant combinations |
| CN110589972A (en) * | 2019-08-16 | 2019-12-20 | 华南农业大学 | Submerged plant surface flow artificial wetland treatment system and method for treating tail water by using same |
-
2020
- 2020-09-09 CN CN202010938265.1A patent/CN112062284A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19630831A1 (en) * | 1996-07-31 | 1998-02-05 | Dernbach Heinrich Gmbh | Multistage biological sewage treatment system |
| CN101314511A (en) * | 2008-04-30 | 2008-12-03 | 华南农业大学 | Baffling type method and system for processing sanitary sewage of horizontal drowned flow artificial wet land |
| CN102190376A (en) * | 2011-05-05 | 2011-09-21 | 西安理工大学 | Integrated flow constructed wetland treatment system |
| CN103819003A (en) * | 2014-02-26 | 2014-05-28 | 桂林理工大学 | Method for treating sewage by utilizing constructed wetland convenient for water sampling |
| CN103951067A (en) * | 2014-04-23 | 2014-07-30 | 广东中大环保科技投资有限公司 | System and method for treating rural sewage by using ecological system based on multi-submerged plant combinations |
| CN110589972A (en) * | 2019-08-16 | 2019-12-20 | 华南农业大学 | Submerged plant surface flow artificial wetland treatment system and method for treating tail water by using same |
Non-Patent Citations (1)
| Title |
|---|
| 谢庭生: "《中国紫色土山丘》", 31 December 2018, 湖南科学技术出版社 * |
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Application publication date: 20201211 |