A river restoration and management system and method

Abstract

The present application discloses a river creek restoration and management system and method, which belongs to the field of ecological restoration. A river creek restoration and management system includes an artificial wetland, which is provided with an inlet and an outlet, the inlet is connected to the front section of the branch creek, and the outlet is connected to the rear section of the branch creek; a biological floating island is provided between the outlet and the branch creek outlet, and the biological floating island is provided with aquatic plants and microbial agents; an aeration device is provided between the outlet and the branch creek outlet, and is used to oxygenate the branch creek water body. The present application has the advantages of saving management costs while ensuring the river creek management effect.

Description

Technical Field

[0001] The present application relates to the field of ecological restoration, and in particular to a system and method for river restoration and management. Background Art

[0002] River and creek ecological restoration is an important part of environmental governance that cannot be ignored. Among the impacts of production and life activities on the environment, rivers and creeks are one of the types that are more susceptible to pollution. River and creek pollution will affect the physical and mental health of the surrounding people and reduce their living standards.

[0003] Generally, river restoration and management will focus on the main stream and tributaries of the river. This is because the main stream flows through a wide range, a large area and a high flow rate, and has a greater impact. Therefore, the focus of restoration and management will be on the main stream. However, the restoration and management of tributaries has also attracted increasing attention because tributaries are often closer to living and production areas. When polluted, the tributaries will collect sewage into the main stream, so the management of the tributaries cannot be ignored.

[0004] At present, one way to manage tributaries is to add sewage treatment equipment, such as MBR integrated sewage treatment equipment. However, sewage treatment equipment not only has high construction costs, but also has high operating and maintenance costs such as electricity consumption, which cannot meet the needs of river management in areas with limited budgets. Summary of the invention

[0005] In order to save management costs while ensuring the river management effect, the present application provides a river restoration and management system and method.

[0006] In the first aspect, the present application provides a river restoration and management system that adopts the following technical solutions:

[0007] A river restoration and management system, comprising:

[0008] An artificial wetland, wherein the artificial wetland is provided with a water inlet and a water outlet, wherein the water inlet is connected to the front section of the branch stream, and the water outlet is connected to the rear section of the branch stream;

[0009] A biological floating island is arranged between the water outlet and the branch outlet, and is provided with aquatic plants and microbial agents; an aeration device is arranged between the water outlet and the branch outlet, and is used to oxygenate the branch water body.

[0010] By adopting the above technical scheme, the section of the branch stream away from the main stream is taken as the front section, and the section close to the main stream is taken as the rear section. Before the water of the branch stream flows into the main stream, part of the water enters the artificial wetland, and the ecological circulation system of the artificial wetland is used for ex situ restoration. The water restored by the artificial wetland is not directly discharged into the main stream, but discharged back to the branch stream, making full use of the process of water flowing in the rear section of the branch stream, thereby purifying the water quality and ecologically supplementing the rear section of the branch stream.

[0011] The aeration device can increase the oxygen content of the branch stream, enhance the biological activity of plankton and aquatic animals in the water, and is conducive to the growth and reproduction of aquatic plants and microbial agents; the branch stream outlet refers to the connection position between the branch stream and the main stream. The biological floating island and the aeration device are set between the outlet and the branch stream outlet. Since the artificial wetland purifies the water quality of the rear section of the branch stream, the difficulty of purifying the water body by the biological floating island is reduced, which helps to solve the problem of difficult growth of aquatic plants and reproduction of microbial agents in the biological floating island, promotes the formation of bacteria-algae symbiotic biofilm, and improves the effect of repair and management. Compared with MBR sewage treatment equipment, the investment cost and operating cost of this river repair and management system are lower, and it can also achieve good repair and management effects.

[0012] Optionally, a plurality of the biological floating islands and the aeration devices are provided, the aeration devices are arranged at intervals along the extension direction of the branch stream, the biological floating islands are arranged at intervals along the extension direction of the branch stream, and the biological floating islands are located between adjacent aeration devices.

[0013] By adopting the above technical solution, the biological floating island and the aeration device are distributed at intervals, so that the aquatic plants and microbial agents of the biological floating island can fully grow and reproduce under the oxygenation effect of the two adjacent aeration devices, thereby playing a purification function.

[0014] Optionally, the biological floating island includes a planting mechanism, a fixing mechanism, a floating mechanism and an adjusting mechanism, the planting mechanism is fixedly connected to the floating mechanism, the planting mechanism is used to carry aquatic plants and microbial agents, the floating mechanism is slidably arranged on the fixing mechanism, and the adjusting mechanism is used to adjust the height of the planting mechanism.

[0015] By adopting the above technical solution, the regulating mechanism makes it possible to adjust the height of aquatic plants and microbial agents in the biological floating island. The efficacy of aquatic plants is affected by photosynthesis. In addition, due to the difference in oxygen content between the upper and lower layers of the water body, it will also affect the respiration of aquatic plants and the reproduction of aerobic bacteria in the microbial agents. Therefore, after height adjustment, the biological floating island can play a greater purification effect.

[0016] Optionally, the adjustment mechanism includes a pulling member, a steering member and a fixing member, the steering member is arranged on the fixing mechanism, one end of the pulling member is connected to the planting mechanism or the floating mechanism, and the other end is connected to the fixing member, and the steering member is used to turn the pulling member close to one end of the fixing member.

[0017] By adopting the above technical solution, the fixing member can be arranged on the river bank of the branch stream, and the planting mechanism or the floating mechanism can be raised and lowered by the movement of the pulling member, thereby adjusting the height of the planting mechanism.

[0018] Optionally, the aquatic plants are selected from one or both of foxtail algae and hydrilla verticillata.

[0019] By adopting the above technical solution, foxtail algae and hydrilla verticillata have strong adaptability and good purification effects on rivers and streams that are originally silty, black and smelly, thereby improving the management effect of the rivers and streams.

[0020] Optionally, the raw materials for preparing the microbial agent include microorganisms, an adhesive and a carrier, the microorganisms include one or more of Bacillus subtilis, purple bacteria, yeast, lactic acid bacteria, Nitrosomonas and Nitrosococcus, the adhesive includes pregelatinized starch and bovine casein, and the carrier includes activated carbon.

[0021] By adopting the above technical scheme, compared with directly adding microorganisms to the planting structure, the method of using carriers to load microorganisms can make the microorganisms less susceptible to river water flow and more stable. In addition, using pregelatinized starch and bovine casein as adhesives can improve the symbiotic relationship between microorganisms and aquatic plants, especially algae, so that the ecosystem of the biological floating island can better achieve pollutant degradation and purification.

[0022] Optionally, the artificial wetland includes a first wetland area and a second wetland area, water in the first wetland area is discharged into the second wetland area, the water inlet is arranged in the first wetland area, the water outlet is arranged in the second wetland area, and the first wetland area is provided with an oxygenation device.

[0023] By adopting the above technical scheme, the artificial wetland is divided into two wetland areas to achieve the purpose of graded purification. The first wetland area will first bear the water with a higher degree of pollution, and the water with a high degree of pollution will not be discharged back to the tributaries too quickly, ensuring that the water entering the artificial wetland can be fully purified, and an oxygenation device is set in the first wetland area to increase the ability of the first wetland area to degrade pollutants.

[0024] In the second aspect, a river restoration and management method provided by the present application adopts the following technical solution:

[0025] A method for repairing and managing a river creek comprises the following steps:

[0026] introducing part of the water of the branch stream into the artificial wetland through the water inlet, and the artificial wetland discharges the water into the branch stream through the water outlet;

[0027] Monitoring the chemical oxygen demand of the water at the water inlet and the water at the water outlet, where the chemical oxygen demand of the water at the water inlet is recorded as CODa, and the chemical oxygen demand of the water at the water outlet is recorded as CODb;

[0028] Start the aeration device to oxygenate the water in the tributary;

[0029] When CODa / CODb<1.6, the aeration capacity of the aeration device for the branch water body is 6~6.5kg / h;

[0030] When CODa / CODb≥1.6, the aeration device has an oxygenation capacity of 3-3.5 kg / h for the branch water body.

[0031] By adopting the above technical scheme, the energy consumption of the aeration device is relatively large, so it is necessary to control the operation process of the aeration device. The treatment method of the present application takes into account the artificial wetland to purify the water quality and ecological supplement of the rear section of the tributary, and therefore adopts the chemical oxygen demand of the water body at the inlet and outlet of the artificial wetland as a parameter, so as to obtain the progress and difficulty of the restoration of the current river water body in the presence of the artificial wetland, and then adjust the oxygenation capacity of the aeration device, that is, adjust the operating power of the aeration device, and more reasonably utilize the energy consumption of the aeration device.

[0032] Optionally, the following steps are also included:

[0033] The height of the planting structure of the biological floating island is adjusted so that the distance between the top of the aquatic plants in the planting structure and the water surface is H1;

[0034] When CODa / CODb<1.6, the aeration device has an oxygenation capacity of 6~6.5kg / h for the branch water body, and H1=1~1.2m;

[0035] When 1.6≤CODa / CODb<1.9, the aeration device has an oxygenation capacity of 4.5-5kg / h for the branch water body, and H1 is adjusted to 0.2-0.4m;

[0036] When CODa / CODb≥1.9, the aeration device has an oxygenation capacity of 3-3.5 kg / h for the branch water body, and H1 is adjusted to 0.5-0.8 m.

[0037] By adopting the above technical solution and adjusting the height of the planting structure, the oxygenation capacity of the aeration device can be adjusted more finely, making the restoration and treatment effect more obvious.

[0038] Optionally, the planting mechanism of the biological floating island is used to carry a microbial agent, and the preparation method of the microbial agent is:

[0039] The pregelatinized starch, milk casein and water are stirred evenly to obtain an adhesive;

[0040] The microorganisms are dispersed in water to obtain a microorganism liquid, a carrier is added into the microorganism liquid to be soaked, the carrier is taken out after the soaking is completed, and then an adhesive is sprayed on the surface of the carrier, and heat-treated and dried to obtain a microorganism agent.

[0041] By adopting the above technical solution, the microorganisms are allowed to penetrate into the carrier by immersion, and then the adhesive is sprayed so that the adhesive is combined with the surface of the carrier, while providing a carbon source for the microorganisms to reproduce, thereby improving the symbiotic relationship and stability between the microorganisms and aquatic plants.

[0042] In summary, this application has the following beneficial effects:

[0043] 1. In this application, before the water of the branch creek flows into the main creek, part of the water enters the artificial wetland, and the ecological circulation system of the artificial wetland is used for ex situ restoration. The water restored by the artificial wetland is not directly discharged into the main creek, but discharged back to the branch creek, making full use of the process of water flowing in the rear section of the branch creek, thereby purifying and ecologically supplementing the water quality in the rear section of the branch creek. The aeration device can increase the oxygen content of the branch creek, enhance the biological activity of plankton and aquatic animals in the water, and is conducive to the growth and reproduction of aquatic plants and microbial agents; the branch creek outlet refers to the connection position between the branch creek and the main creek, and the biological floating island and the aeration device are both arranged between the outlet and the branch creek outlet. Since the artificial wetland purifies the water quality of the rear section of the branch creek, the difficulty of purifying the water body by the biological floating island is reduced, which helps to solve the problem of difficult growth of aquatic plants and reproduction of microbial agents in the biological floating island, promotes the formation of bacteria-algae symbiotic biofilm, and improves the effect of restoration and management. Compared with MBR sewage treatment equipment, the river creek restoration and management system has lower investment cost and operation cost, and can also obtain good restoration and management effect.

[0044] 2. The treatment method of the present application takes into account the purification and ecological supplement of the water quality of the rear section of the tributary by artificial wetlands. Therefore, the chemical oxygen demand of the water body at the inlet and outlet of the artificial wetland is used as a parameter to obtain the progress and difficulty of the restoration of the current river water body in the presence of the artificial wetland, and then adjust the oxygenation capacity of the aeration device, that is, adjust the operating power of the aeration device, and make more reasonable use of the energy consumption of the aeration device. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a plan view of the river restoration and management system of Example 1 of the present application.

[0046] Figure 2 This is a plan view of the biological floating island of Example 1 of the present application.

[0047] Description of reference numerals:

[0048] 1. Branch spring; 2. Main spring; 3. Artificial wetland; 31. First wetland area; 32. Second wetland area; 33. Water inlet; 34. Water outlet; 35. Oxygenation device; 4. Biological floating island; 41. Fixed column; 42. Floating plate; 43. Planting pot; 44. Pull rope; 45. Fixed pulley; 46. Winch; 5. Aeration device. DETAILED DESCRIPTION

[0049] The following is combined with Figure 1-2 This application is described in further detail.

[0050] Example 1

[0051] Embodiment 1 of the present application discloses a system for repairing and managing a river. Figure 1 As shown, a river creek restoration and management system includes an artificial wetland 3, a biological floating island 4 and an aeration device 5. The artificial wetland 3 is arranged beside a branch creek 1, and the biological floating island 4 and the aeration device 5 are both arranged in the branch creek 1. In this embodiment, the end of the branch creek 1 is connected to the main creek 2.

[0052] The artificial wetland 3 includes a first wetland area 31 and a second wetland area 32. The first wetland area 31 and the second wetland area 32 are provided with a connecting port so that the water in the first wetland area 31 can be discharged into the second wetland area 32. The water can be pumped through a pipeline or discharged into the second wetland area 32 by using the terrain height difference. This embodiment specifically uses the terrain height difference to reduce power consumption. The two wetland areas are used for graded purification, so that the water in the branch stream 1 stays in the artificial wetland 3 for a longer time, and the water with a high degree of pollution will not be discharged back to the branch stream 1 too quickly.

[0053] The section of the branch spring 1 away from the main spring 2 is the front section, and the section close to the main spring 2 is the back section. The first wetland area 31 is provided with a water inlet 33, which is connected to the front section of the branch spring 1. The water inlet 33 is provided with a water pump, and the water in the front section of the branch spring 1 is introduced into the first wetland area 31 through the water pump; the second wetland area 32 is provided with a water outlet 34, which is connected to the back section of the branch spring 1. The water outlet 34 is provided with a sluice, and the water in the second wetland area 32 is discharged into the back section of the branch spring 1 through the control of the sluice.

[0054] Specifically, artificial wetland 3 is planted with submerged plants, which are used to absorb nutrient-rich substances. Omnivorous fish, such as carp and crucian carp, are also placed in artificial wetland 3. Omnivorous fish feed on and consume suspended matter and organic debris in the water, thereby improving the turbidity of the water. Therefore, artificial wetland 3 forms a relatively rich ecosystem. The water of branch stream 1 is purified and ecologically supplemented after entering artificial wetland 3. When the water is discharged from artificial wetland 3 into the rear section of branch stream 1, not only the pollution level of branch stream 1 is diluted, but also the beneficial algae and zooplankton in the water discharged from artificial wetland 3 can swallow the bacteria and debris of branch stream 1, thereby further improving the water quality of branch stream 1 and achieving good restoration and management effects.

[0055] Furthermore, the first wet area 31 is provided with an oxygenating device 35, which is specifically an impeller aerator. Since the first wet area 31 is first subjected to water with a higher degree of pollution, increasing the oxygen content of the first wet area 31 helps to improve the ability of the first wet area 31 to degrade pollutants.

[0056] The connecting point between the branch spring 1 and the main spring 2 is the outlet of the branch spring 1, and the biological floating island 4 and the aeration device 5 are both arranged between the outlet 34 and the outlet of the branch spring 1, so that the biological floating island 4 and the aeration device 5 can utilize the water body restored by the artificial wetland 3 in the process of purifying the water quality of the branch spring 1, thereby improving the restoration effect of the biological floating island 4 and the aeration device 5.

[0057] The ecological circulation system of the artificial wetland 3 is used for ex situ restoration, and the water restored by the artificial wetland 3 is not directly discharged into the main stream 2, but discharged back to the branch stream 1, making full use of the process of water flowing in the rear section of the branch stream 1. In this process, the water discharged from the artificial wetland 3 purifies the water quality of the rear section of the branch stream 1, thereby reducing the difficulty of purifying the water by the biological floating island 4, which helps to solve the problems of difficult growth of aquatic plants and reproduction of microbial agents in the biological floating island 4. In addition, compared with the MBR sewage treatment equipment, the MBR sewage treatment equipment has high energy consumption and maintenance costs, while the river and stream restoration and management system of the present application has lower investment costs and operating costs, and can also achieve good restoration and management effects.

[0058] Multiple biological floating islands 4 and aeration devices 5 are provided. The aeration devices 5 are arranged at intervals along the extension direction of the branch stream 1, and the interval can be 20 to 30 meters. In this embodiment, it is specifically 20 meters. Similarly, the biological floating islands 4 are arranged at intervals along the extension direction of the branch stream 1, and the interval can be 20 to 30 meters. In this embodiment, it is specifically 20 meters, and the biological floating islands 4 are located between adjacent aeration devices 5. The aquatic plants and microbial agents of the biological floating islands 4 can fully grow and reproduce under the oxygenation effect of the two adjacent aeration devices 5, thereby exerting a purification function.

[0059] The aeration device 5 is specifically an impeller aerator, which utilizes an impeller to stir the water body, splashing water to dissolve more dissolved oxygen in the water body, and can rapidly increase the oxygen content of the water body.

[0060] like Figure 2 As shown, the biological floating island 4 includes a planting mechanism, a fixing mechanism, a floating mechanism and an adjusting mechanism. The fixing mechanism includes a fixing column 41, the bottom of which is fixedly installed on the bottom of the branch 1. The floating mechanism includes a floating plate 42, which is slidably connected to the fixing column 41. The planting mechanism includes a planting pot 43, which is filled with nutrient mud, aquatic plants are planted through the nutrient mud, and microbial agents are placed in the planting pot 43.

[0061] The adjusting mechanism includes a pulling member, a steering member and a fixing member. The pulling member can be specifically a pull rope 44, one end of which is fixedly connected to the floating plate 42. The steering member can be specifically a fixed pulley 45, which is installed on the top of the fixed column 41. The middle part of the pull rope 44 passes around the fixed pulley 45 along 90°, so that a section of the pull rope 44 close to the floating plate 42 is vertically arranged, and a section away from the floating plate 42 is horizontally arranged. The fixing member is installed on the bank of the branch stream 1. The fixing member can be a winch 46. The winch 46 winches the pull rope 44, drives the pull rope 44 to move, thereby realizing the lifting and lowering of the floating plate 42, and further achieving the purpose of adjusting the height of the planting mechanism.

[0062] Since there is a difference in oxygen content between the upper and lower layers of the water body in Branch 1, it will also affect the respiration of aquatic plants and the reproduction of aerobic bacteria in microbial agents. Therefore, after high regulation, aquatic plants and microbial agents can play a greater purification effect.

[0063] The aquatic plants selected are foxtail algae and hydrilla verticillata, which have strong environmental adaptability and have a good treatment effect on black and smelly rivers. Specifically, foxtail algae and hydrilla verticillata absorb nutrients, enrich heavy metals, transform and degrade organic matter through filtration sedimentation, photosynthesis and respiration, and cooperate with microbial agents to form a bacteria-algae symbiotic biofilm, forming a diverse growth environment to achieve the effect of clear water.

[0064] The microbial agent is prepared by using microbial bacteria, an adhesive and a carrier. The specific preparation method is as follows:

[0065] Step 1: Mix pregelatinized starch, bovine casein and water in a mass ratio of 10:1:20, stir evenly, and obtain an adhesive.

[0066] Step 2: Collect Bacillus subtilis, purple bacteria, yeast and nitrosococcus as microorganisms, disperse the microorganisms in water to obtain a microbial liquid, wherein the concentration of Bacillus subtilis in the microbial liquid is 7.59×10 13 / mL, the concentration of purple bacteria is 2.23×10 13 / mL, the concentration of yeast was 4.6×10 13 / mL, and the concentration of Nitrosococcus was 1.33×10 13 / mL; add the carrier into the microbial liquid and soak it, the carrier is specifically activated carbon, take out the carrier after soaking, and then spray the adhesive on the surface of the carrier, dry it with hot air to obtain the microbial agent, wherein the mass ratio of the carrier to the adhesive is 1:0.8.

[0067] The use of carriers to load microorganisms can make it less likely for the microorganisms to be washed away from the planting structure by river water, and the use of pregelatinized starch and bovine casein as adhesives can improve the symbiotic relationship between the microorganisms and foxtail algae and verticillium, so that the ecosystem of the biological floating island 4 can better achieve pollutant degradation and purification.

[0068] like Figure 1 As shown, this embodiment 1 also discloses a river repair and management method, comprising the following steps:

[0069] Part of the water of the branch stream 1 is introduced into the artificial wetland 3 through the water inlet 33 , and the artificial wetland 3 discharges the water into the branch stream 1 through the water outlet 34 .

[0070] The chemical oxygen demand of the water at the water inlet 33 and the water at the water outlet 34 is monitored. The chemical oxygen demand of the water at the water inlet 33 is recorded as CODa, and the chemical oxygen demand of the water at the water outlet 34 is recorded as CODb.

[0071] Specifically, the water monitoring position of the water inlet 33 is a position starting from the water pump at the water inlet 33 and extending 5 meters toward the front section of the branch stream 1. The water monitoring position of the water outlet 34 is a position starting from the water gate at the water outlet 34 and extending 5 meters toward the rear section of the branch stream 1.

[0072] Keep the top of the aquatic plants in the planting structure 0.8m away from the water surface.

[0073] The aeration device 5 is started to oxygenate the water in the branch stream 1.

[0074] Since the aeration device consumes a lot of energy, it is necessary to control the operating power of the aeration device to reduce the energy consumption of the aeration device while ensuring good repair and treatment effects, thereby reducing the operating cost of the repair and treatment system.

[0075] When CODa / CODb<1.6, the aeration capacity of the aeration device for the branch water body is 6~6.5kg / h;

[0076] When CODa / CODb≥1.6, the aeration device's oxygenation capacity for branch water bodies is 3 to 3.5 kg / h.

[0077] The greater the oxygenation capacity of the aeration device, the greater the operating power of the aeration device. The above adjustment method uses the chemical oxygen demand of the water body at the inlet and outlet as parameters to obtain the restoration progress and difficulty of the current tributary water body in the presence of the artificial wetland, thereby combining the management capacity of the artificial wetland with the management capacity of the biological floating island and the aeration device, giving full play to the role of the purified water discharged from the artificial wetland in promoting the management capacity of the biological floating island and the aeration device, thereby greatly improving the management efficiency.

[0078] Application Examples

[0079] Governance of Sanya Creek in Sanshui District, Foshan City: Sanya Creek is a tributary that flows into Zuo'an Creek. Its main source of pollution is the discharge of effluent from surrounding agricultural breeding. The COD of river water at the connection point between Sanya Creek and Zuo'an Creek is 116-135 mg / L, and the total amount of ammonia nitrogen is 10-15 mg / L, which is far below the Class V water quality standard.

[0080] The river creek restoration and management system and the river creek restoration and management method of this embodiment are applied to the downstream section of Sanya Creek, and the length of the downstream section is 350m.

[0081] For example: When CODa=126mg / L and CODb=82mg / L are measured in real time, the requirement of CODa / CODb<1.6 is met, and the aeration capacity of the aeration device for the branch water body is adjusted to 6kg / h.

[0082] Another example: when CODa=132mg / L and CODb=67mg / L are measured in real time, the requirement of CODa / CODb≥1.6 is met, and the aeration capacity of the aeration device for the branch water body is adjusted to 3kg / h.

[0083] The river creek repair and management system and method of this embodiment is operated after the dredging work of the bottom of Sanya Creek is completed. Before and during the operation, the water quality of the connection between Sanya Creek (i.e., the branch creek) and Zuo'an Creek (i.e., the main creek) is sampled. The sampling frequency is every day. The test results on the day when the water quality meets the V-class water requirements and on the 30th day are recorded as shown in Table 1:

[0084] Table 1

[0085] Before running Day 20 of operation Day 30 of operation Ammonia nitrogen (mg / L) 12.66 1.96 1.65 Chemical oxygen demand COD (mg / L) 105.25 36.78 32.38

[0086] Surface Water Environmental Quality Standards

[0087] index Class V water index Ammonia nitrogen <2.0mg / L Chemical oxygen demand (COD) <40mg / L

[0088] As can be seen from Table 1, the river restoration and management system and method of this embodiment can be operated for 30 days to significantly reduce the ammonia nitrogen content and chemical oxygen demand of the river water body, meeting the requirements of Class V water in the "Surface Water Environmental Quality Standards".

[0089] In addition, this embodiment does not need to use the high oxygenation power mode of the aeration device throughout the entire process, which greatly reduces energy consumption and thus saves costs.

[0090] Example 2

[0091] The difference between this embodiment and Embodiment 1 is that the river repair and management method of this embodiment is different.

[0092] Specifically, a river restoration and management method includes the following steps:

[0093] Part of the water from the branch stream is introduced into the artificial wetland through the water inlet, and the artificial wetland discharges the water into the branch stream through the water outlet.

[0094] The chemical oxygen demand of the water at the water inlet and the water outlet is monitored. The chemical oxygen demand of the water at the water inlet is recorded as CODa, and the chemical oxygen demand of the water at the water outlet is recorded as CODb.

[0095] Specifically, the water body monitoring position of the water inlet is the position starting from the water inlet pump and extending 5 meters towards the front section of the branch stream. The water body monitoring position of the water outlet is the position starting from the water outlet sluice and extending 5 meters towards the rear section of the branch stream.

[0096] Start the aeration device to oxygenate the water in the tributary.

[0097] The height of the planting structure of the biological floating island is adjusted so that the distance between the top of the aquatic plants in the planting structure and the water surface is H1.

[0098] When CODa / CODb<1.6, the aeration capacity of the aeration device for the branch water body is 6~6.5kg / h, and H1=1~1.2m;

[0099] When 1.6≤CODa / CODb<1.9, the aeration capacity of the aeration device for the branch water body is 4.5~5kg / h, and H1=0.2~0.4m;

[0100] When CODa / CODb≥1.9, the aeration device has the oxygenation capacity of 3-3.5kg / h for the branch water body, and H1 is adjusted to 0.5-0.8m.

[0101] The above treatment method can refine the adjustment of the oxygenation capacity of the aeration device, and use the synergistic relationship between the oxygenation capacity of the aeration device and the height of the planting mechanism to achieve more efficient restoration and treatment. In actual application, it is found that the lower the oxygenation capacity of the aeration device, the closer the planting mechanism does not necessarily need to be to the water surface. This embodiment cooperates with the oxygenation level of the median case of 1.6≤CODa / CODb<1.9 to obtain a better and more energy-saving treatment effect.

[0102] Application Examples

[0103] This embodiment is also specifically applied in Sanyayong.

[0104] The application of this embodiment is 7 months after the application of embodiment 1. Specifically, the total application time of embodiment 1 is 1 month, and then the application is stopped for 6 months.

[0105] For example: When CODa=110mg / L and CODb=73mg / L are measured in real time, the requirement of CODa / CODb<1.6 is met, and the aeration capacity of the aeration device for the branch water body is adjusted to 6kg / h, and H1=1m is adjusted.

[0106] Another example: When CODa=115mg / L and CODb=65mg / L are measured in real time, meeting the requirement of 1.6≤CODa / CODb<1.9, the aeration device is adjusted to increase oxygen to 6kg / h for the branch water body, and H1=0.2m is adjusted.

[0107] Another example: when CODa = 103 mg / L and CODb = 47 mg / L are measured in real time, meeting the requirement of CODa / CODb ≥ 1.9, the aeration device is adjusted to increase oxygen to 6 kg / h for the branch water body, and H1 is adjusted to 0.5 m.

[0108] Before and during the operation of this embodiment, the water quality of the connection between the branch spring and the main spring is sampled every day, and the test results on the day when the water quality meets the Class V water requirements and on the 30th day are recorded as shown in Table 2:

[0109] Table 2

[0110]

[0111]

[0112] From the comparison between Table 1 and Table 2, it can be seen that by operating the river and creek restoration and management system and method according to the present embodiment, the tributary water body can meet the requirements of Class V water in the "Surface Water Environmental Quality Standards" on the 12th day, reach the purification standard more quickly, and the water quality is significantly improved on the 30th day.

[0113] In addition, after running for 30 days, the total energy consumption of the aeration device of this embodiment increased by only 10.2% compared with that of embodiment 1, so the energy consumption did not change much and the water quality was significantly improved.

[0114] Comparative Example 1

[0115] The difference between this comparative example and Example 1 is that the aeration device maintains an oxygenation capacity of 6 kg / h for the branch water body.

[0116] Application Examples

[0117] Governance of Hengyi Creek in Sanshui District, Foshan City: Hengyi Creek is another tributary that flows into Zuo'an Creek. Its main pollution source is the discharge of effluent from surrounding agricultural breeding. The width and flow of Hengyi Creek are similar to those of Sanya Creek. The COD of river water at the connection point between Hengyi Creek and Zuo'an Creek is 108-131 mg / L, and the total ammonia nitrogen is 9-16 mg / L, which is far below the Class V water quality standard.

[0118] The river creek restoration and management system and river creek restoration and management method of this comparative example were applied to the downstream section of Sanya Creek. The length of the downstream section was 400m, and the area of ​​artificial wetlands, the number of biological floating islands, and the number of aeration devices were the same as those in Example 1.

[0119] The river creek repair and management system and method of this comparative example is put into operation after the dredging work of the bottom of Hengyi creek is completed. Before and during the operation, the water quality of the connection between Hengyi creek (i.e., branch creek) and Zuo'an creek (i.e., main creek) is sampled. The sampling frequency is every day. The test results on the day when the water quality meets the requirements of Class V water and on the 30th day are recorded as shown in Table 3:

[0120] Table 3

[0121] Before running Day 20 of operation Day 30 of operation Ammonia nitrogen (mg / L) 10.34 1.88 1.68 Chemical oxygen demand COD (mg / L) 116.55 38.26 35.02

[0122] As can be seen from Table 1, the system and method for river restoration and management of this comparative example were operated for 30 days. Although the ammonia nitrogen content and chemical oxygen demand of the river water body can meet the requirements of Class V water in the "Surface Water Environmental Quality Standard", the purification degree of the river water body is similar to that of Example 1. Moreover, since the aeration device is maintained in a high-power operation state with high oxygenation capacity, the energy consumption of this comparative example is 32.6% more than that of the aeration device of Example 1 on the 30th day of operation. The energy consumption is large and does not conform to the concept of environmentally friendly river restoration.

[0123] This specific implementation manner is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the specific implementation manner as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A method for repairing and managing a river creek, characterized by: The method adopts a river restoration and management system, which includes: An artificial wetland (3), wherein the artificial wetland (3) is provided with a water inlet (33) and a water outlet (34), wherein the water inlet (33) is connected to the front section of the branch spring (1), and the water outlet (34) is connected to the rear section of the branch spring (1); A biological floating island (4) is arranged between the water outlet (34) and the outlet of the branch stream (1), and the biological floating island (4) is provided with aquatic plants and microbial agents; an aeration device (5), arranged between the water outlet (34) and the outlet of the branch stream (1), and used for oxygenating the water body of the branch stream (1); A plurality of the biological floating islands (4) and the aeration devices (5) are provided, the aeration devices (5) are arranged at intervals along the extension direction of the branch stream (1), the biological floating islands (4) are arranged at intervals along the extension direction of the branch stream (1), and the biological floating islands (4) are located between adjacent aeration devices (5); The biological floating island (4) comprises a planting mechanism, a fixing mechanism, a floating mechanism and an adjusting mechanism, wherein the planting mechanism is fixedly connected to the floating mechanism, the planting mechanism is used to carry aquatic plants and microbial agents, the floating mechanism is slidably arranged on the fixing mechanism, and the adjusting mechanism is used to adjust the height of the planting mechanism; The governance method comprises the following steps: A portion of the water of the branch stream (1) is introduced into the artificial wetland (3) through the water inlet (33), and the artificial wetland (3) discharges the water into the branch stream (1) through the water outlet (34); Monitoring the chemical oxygen demand of the water at the water inlet (33) and the water at the water outlet (34), wherein the chemical oxygen demand of the water at the water inlet (33) is recorded as CODa, and the chemical oxygen demand of the water at the water outlet (34) is recorded as CODb; Starting the aeration device (5) to oxygenate the water in the branch stream (1); The height of the planting structure of the biological floating island (4) is adjusted so that the distance between the top of the aquatic plants in the planting structure and the water surface is H1; When CODa / CODb<1.6, the aeration capacity of the aeration device (5) for the water body of the branch stream (1) is 6~6.5kg / h, and H1 is adjusted to 1~1.2m; When 1.6≤CODa / CODb<1.9, the aeration capacity of the aeration device (5) for the water body of the branch stream (1) is 4.5~5kg / h, and H1 is adjusted to 0.2~0.4m; When CODa / CODb≥1.9, the aeration device (5) has an oxygenation capacity of 3-3.5 kg / h for the water body of the branch stream (1), and H1 is adjusted to 0.5-0.8 m.

2. A method for repairing and managing a river creek according to claim 1, characterized in that: The adjustment mechanism includes a pulling member, a steering member and a fixing member. The steering member is arranged on the fixing mechanism. One end of the pulling member is connected to the planting mechanism or the floating mechanism, and the other end is connected to the fixing member. The steering member is used to turn the pulling member close to one end of the fixing member.

3. A method for repairing and managing a river creek according to claim 1, characterized in that: The aquatic plants are selected from one or two of foxtail algae and hydrilla verticillata.

4. A method for repairing and managing a river creek according to claim 1, characterized in that: The raw materials for preparing the microbial agent include microorganisms, an adhesive and a carrier. The microorganisms include one or more of Bacillus subtilis, purple bacteria, yeast, lactic acid bacteria, nitrosomonas and nitrosococcus. The adhesive includes pregelatinized starch and bovine casein. The carrier includes activated carbon.

5. A method for repairing and managing a river creek according to claim 1, characterized in that: The artificial wetland (3) comprises a first wetland area (31) and a second wetland area (32); water in the first wetland area (31) is discharged into the second wetland area (32); the water inlet (33) is arranged in the first wetland area (31); the water outlet (34) is arranged in the second wetland area (32); and the first wetland area (31) is provided with an oxygenation device (35).

6. A method for repairing and regulating a river according to claim 1, characterized in that: The planting mechanism of the biological floating island (4) is used to carry a microbial agent, and the preparation method of the microbial agent is as follows: The pregelatinized starch, milk casein and water are stirred evenly to obtain an adhesive; The microorganisms are dispersed in water to obtain a microorganism liquid, a carrier is added into the microorganism liquid to be soaked, the carrier is taken out after the soaking is completed, and then an adhesive is sprayed on the surface of the carrier, and heat-treated and dried to obtain a microorganism agent.

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