Method for automatically collecting and naturally purifying non-point source pollution

Abstract

The invention belongs to the technical field of wastewater treatment, and particularly relates to a method for automatically collecting and naturally purifying non-point source pollution. The method for automatically collecting and naturally purifying the non-point source pollution comprises the following steps: determining the initial rainwater quantity in the non-point source pollution according to a formula 1; q is the amount of rainwater in the initial stage of non-point source pollution, and the unit is m < 3 >; f is the catchment area of the non-point source pollution area, and the unit is hm < 2 >; # imgabs 1 # is a runoff coefficient; t is water collection time, and the unit is min; q is rainstorm intensity, and the unit is L / s.hm < 2 >; the initial rainwater is collected to the storage and distribution system through the collection system, and collected initial rainwater is obtained; and purifying the collected initial rainwater by using a natural purification system to obtain purified rainwater. The water quantity of initial rainwater is quantified and distinguished to reduce the sewage treatment capacity, the wastewater treatment method does not need to be operated by personnel, the operation and maintenance cost is low, non-point source pollution in rural areas can be collected and purified, and pollution to the ecological environment is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of wastewater treatment, and in particular relates to a method for automatic collection and natural purification of surface source pollution. Background Art

[0002] Applied pesticides and fertilizers, free-range livestock and poultry manure, and untreated agricultural production waste, domestic garbage and wastewater are all direct factors causing non-point source pollution. Non-point source pollution enters the surface and groundwater bodies under the erosion of rainwater and causes pollution, especially the high concentration of pollutants in the initial rainwater, which will cause serious pollution to the soil, water bodies and the production and living environment. After the initial rainwater is washed, the surface becomes relatively clean, and the pollution level of the later rainwater is low, which has less impact on the water quality of the receiving water body and does not need to be treated. At present, most of the methods for treating initial rainwater do not provide a method for determining the amount of initial rainwater. If the amount of initial rainwater is not determined, the treatment of initial rainwater is very blind. Therefore, distinguishing initial rainwater from later rainwater and automatically collecting initial rainwater has become a key issue. Summary of the invention

[0003] In view of this, the present invention provides a method for automatic collection and natural purification of surface source pollution. The method provided by the present invention can accurately separate initial rainwater from later rainwater, better treat initial rainwater, and reduce pollution to the ecological environment.

[0004] In order to solve the above technical problems, the present invention provides a method for automatic collection and natural purification of non-point source pollution, comprising the following steps:

[0005] Determine the initial rainwater volume in non-point source pollution according to formula 1;

[0006]

[0007] Among them, Q is the initial rainwater volume in non-point source pollution, unit is m 3 ; F is the catchment area of ​​non-point source pollution area, unit is hm2; is the runoff coefficient; T is the water collection time, in min; q is the rainstorm intensity, in L / s·hm2;

[0008] Using the collection system to collect the initial rainwater to the storage and diversion system, the collected initial rainwater is obtained;

[0009] The collected initial rainwater is purified by using a natural purification system to obtain purified rainwater.

[0010] Preferably, the storage and diversion system includes an inlet channel 1, an overflow facility 2, a slag retaining facility 3, an inlet control facility 4, a sedimentation tank 5, a water storage tank 6, an outlet control facility 7 and an outlet channel 8 which are connected in series in sequence.

[0011] Preferably, the capacity of the water storage tank 6 is greater than or equal to the initial rainwater volume.

[0012] Preferably, the collection system includes an existing water system and / or an existing ditch in the area to be treated.

[0013] Preferably, the existing ditch includes a water diversion weir or a water diversion ditch.

[0014] Preferably, the natural purification system comprises a natural wetland or an artificial wetland.

[0015] Preferably, F is determined based on the distribution of non-point source pollution in the area to be treated.

[0016] Preferably, the Determined based on the topography and rainfall characteristics of the area to be treated.

[0017] Preferably, the T is 15 min.

[0018] Preferably, the q is calculated according to GB50016-2006.

[0019] The present invention provides a method for automatically collecting and naturally purifying non-point source pollution, comprising the following steps:

[0020] Determine the initial rainwater volume in non-point source pollution according to formula 1; Formula 1; where Q is the initial rainwater volume in non-point source pollution, in m 3 ; F is the catchment area of ​​non-point source pollution area, unit is hm2; is the runoff coefficient; T is the water collection time, in min; q is the rainstorm intensity, in L / s·hm2; the initial rainwater is collected by the collection system to the storage and diversion system to obtain the collected initial rainwater; the collected initial rainwater is purified by the natural purification system to obtain purified rainwater. The present invention quantifies the amount of non-point source polluted water brought by rainwater runoff, realizes the accurate and effective separation and storage of initial rainwater and later rainwater, avoids the mixing of polluted initial rainwater and unpolluted later rainwater, reduces the amount of sewage treatment; and reduces the cost of sewage treatment. The method provided by the present invention can realize the effective collection and purification of non-point source pollution, and reduce the pollution to the ecological environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of a process for automatically collecting and naturally purifying surface pollution according to an embodiment;

[0022] Figure 2 It is a structural schematic diagram of the storage and diversion system in the embodiment;

[0023] Figure 3It is an AA cross-sectional view of the storage and diversion system in the embodiment;

[0024] Figure 2 , 3 Among them, 1 is the inlet channel, 2 is the overflow facility, 3 is the slag blocking facility, 4 is the inlet control facility, 5 is the sedimentation tank, 6 is the water storage tank, 7 is the outlet control facility, and 8 is the outlet channel. DETAILED DESCRIPTION

[0025] The present invention provides a method for automatically collecting and naturally purifying non-point source pollution, comprising the following steps:

[0026] Determine the initial rainwater volume in non-point source pollution according to formula 1;

[0027]

[0028] Among them, Q is the initial rainwater volume in non-point source pollution, unit is m 3 ; F is the catchment area of ​​non-point source pollution area, unit is hm2; is the runoff coefficient; T is the water collection time, in min; q is the rainstorm intensity, in L / s·hm2;

[0029] Using the collection system to collect the initial rainwater to the storage and diversion system, the collected initial rainwater is obtained;

[0030] The collected initial rainwater is purified by using a natural purification system to obtain purified rainwater.

[0031] The present invention determines the initial rainwater volume in non-point source pollution according to Formula 1;

[0032]

[0033] Among them, Q is the initial rainwater volume in non-point source pollution, unit is m 3 ; F is the catchment area of ​​non-point source pollution area, unit is hm2; is the runoff coefficient; T is the water collection time, in min; q is the rainstorm intensity, in L / s·hm2;

[0034] As a specific implementation of the present invention, the non-point source pollution may be rural non-point source pollution, and F may be determined based on the distribution of non-point source pollution sources in the area to be treated; the method for determining the catchment area of ​​the non-point source pollution area may include the following steps:

[0035] S101. Investigate the population and domestic sewage discharge in the area to be treated;

[0036] S102. Investigate the pollution from aquaculture and planting sources in the areas to be treated;

[0037] S103. Investigate and analyze the water quality in the area to be treated and determine the scope of non-point source sewage.

[0038] The present invention has no special requirements on the investigation method in steps S101, S102 and S103, and conventional methods in the art may be used.

[0039] As a specific embodiment of the present invention, the It can be determined based on the topography and rainfall characteristics of the area to be treated; It can be 0.2 to 0.9, or 0.3 to 0.8.

[0040] As a specific implementation of the present invention, the T may be 15 min.

[0041] As a specific implementation of the present invention, the q can be calculated according to the "Outdoor Drainage Design Code" GB50016-2006 (2014 edition).

[0042] After determining the amount of initial rainwater, the present invention uses a collection system to collect the initial rainwater into a storage and diversion system to obtain collected initial rainwater. As a specific embodiment of the present invention, the collection system may include an original water system and / or an original ditch in the area to be treated; the original ditch may include a water diversion weir or a water diversion ditch; the initial rainwater flows to the storage and diversion system through the collection system. The present invention can also combine the collection system with flood control and drainage facilities, and the inlet channel can be used for flood control and drainage when necessary. As a specific embodiment of the present invention, the storage and diversion system may include an inlet channel 1, an overflow facility 2, a slag blocking facility 3, an inlet control facility 4, a sedimentation tank 5, a water storage tank 6, an outlet control facility 7 and an outlet channel 8 connected in series in sequence, and a water level sensing controller or a flow sensing controller may be provided in the inlet control facility 4. The present invention has no special limitation on the inlet channel 1, and a conventional method in the art may be used; the outlet of the inlet channel 1 may be connected to the inlet of the sedimentation tank 5, and the outlet arranged at the bottom of the water storage tank 6 is connected to the inlet of the outlet channel 8.

[0043] As a specific embodiment of the present invention, the slag interception facility 3 can intercept the solid suspended matter entering the storage and diversion system; the sedimentation tank 5 can precipitate and filter the silt and the pollutants attached to the silt; the water storage tank 6 is used to store the collected initial rainwater, and the capacity of the water storage tank 6 can be greater than or equal to the initial rainwater volume. When the initial rainwater volume reaches the initial rainwater volume calculated according to formula 1, the water level sensing controller or the flow sensing controller is used to automatically close the water inlet control facility 4. When the water inlet control facility 4 is closed, the subsequent rainwater flows out from the overflow facility 2 and merges into the ditch, canal or river channel of the source; the water outlet control facility 7 can control the sewage to enter the natural purification system from the water outlet canal 8 in batches for purification. When the sewage is processed in the subsequent purification system, the water level drops, and the water level sensing controller or the flow sensor in the water inlet control facility 4 sends a command to open the water inlet control facility 4, waiting for the next sewage to enter. The present invention can set the water storage tank 6 in a low-lying area where rainwater gathers, and the initial rainwater can flow into the water storage tank 6 by gravity. The present invention can circulate and treat the initial rainwater generated by non-point source pollution in the above manner.

[0044] After obtaining the collected initial rainwater, the present invention utilizes a natural purification system to purify the collected initial rainwater to obtain purified rainwater. As a specific embodiment of the present invention, the natural purification system may include a natural wetland or an artificial wetland. As a specific embodiment of the present invention, the processing capacity of the wetland is constructed according to the initial rainwater volume, the water quality of the inlet (initial rainwater) and the water quality requirements of the outlet (purified rainwater), and is designed in accordance with relevant wetland construction standards and specifications. The present invention can construct a natural purification system according to on-site conditions. If there are available ponds or depressions, and the area meets the processing capacity requirements, natural wetlands are constructed in the ponds and depressions. If there are no available ponds or depressions, artificial wetlands are constructed.

[0045] Figure 1 This is a flow chart of a method for automatically collecting and naturally purifying surface pollution according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the storage distribution system. Figure 3 It is the AA cross-sectional view of the storage and diversion system, where 1 is the inlet channel, 2 is the overflow facility, 3 is the slag blocking facility, 4 is the inlet control facility, 5 is the sedimentation tank, 6 is the water storage tank, 7 is the outlet control facility, and 8 is the outlet channel.

[0046] The present invention makes full use of existing ditches, canals, ponds, depressions, etc. in the treatment area, such as rural areas, to construct natural wetlands or artificial wetlands, reduce construction costs, and save land; sewage is automatically diverted and naturally purified without the need for human operation, is simple to build, and has very low operation and maintenance costs.

[0047] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0048] Example 1

[0049] according to Figure 1 The process shown in the figure treats the non-point source pollution caused by the initial rainwater runoff in Jima Village, Guilin City. The specific steps are as follows:

[0050] In step S1, based on the survey results of the distribution of non-point source pollution sources in the region, the key areas for the collection of non-point source pollution sewage are determined, including the following methods:

[0051] S101. Survey on the population of villages in the region and survey on domestic sewage discharge;

[0052] S102. Investigation of pollution from aquaculture and planting sources;

[0053] S103. Investigate and analyze water quality in the region and determine the scope of non-point source sewage;

[0054] Investigate the population of the village to understand the amount of domestic sewage discharged; Investigate whether there are sewage pipe networks and treatment facilities in rural areas. If not, it is necessary to build rural domestic sewage treatment facilities; Investigate the livestock and poultry breeding situation. If so, it is necessary to build sewage treatment facilities and return the effluent to the fields for agricultural use; According to the planting situation, determine the scope of pollution collection to facilitate the calculation of sewage volume; Investigate the indicators of dissolved oxygen, permanganate index, COD, BOD5, NH3-N, TP, and TN in the water quality in the area to understand the scope of pollution; Understand the water function zoning and understand the required river water quality in the area. According to the investigation and monitoring, the initial rainwater quality is listed in Table 1.

[0055] Table 1 Initial rainwater quality (unit: mg / L)

[0056] Pollutants DO <![CDATA[COD CR ]]> <![CDATA[NH3-N]]> TP TN SS Initial Rain 6.9 36 1.48 0.31 1.51 55

[0057] Among them, DO is dissolved oxygen, COD CR is the chemical oxygen demand, NH3-N is ammonia nitrogen, TP is the total amount of phosphorus compounds in all forms in the water sample (total) phosphorus, TN is the total nitrogen content in the water sample, and SS is the solid matter suspended in the water (suspended matter).

[0058] According to the data in Table 1, the water quality in the initial rainwater stage is Class V surface water quality. The water function zoning in this area requires that the water quality be Class III surface water quality, which will cause pollution to the downstream receiving water bodies.

[0059] In step S2, the amount of water collected by non-point source pollution in the area is determined, including the following methods:

[0060] S201. Determine the runoff coefficient based on the survey of the topography and rainfall conditions in the region;

[0061] S202. Calculate and determine the annual maximum rainstorm intensity after investigating and analyzing the rainfall situation.

[0062] Calculate the initial rainwater volume according to formula 1:

[0063]

[0064] Among them, Q is the initial rainwater volume in non-point source pollution, and the calculated result is 5470m 3 ; F is the catchment area of ​​non-point source pollution area, which is 2.75.hm2; is the runoff coefficient, which is 0.6; T is the water collection time, which is 15 min; q is the rainstorm intensity, which is 221 L / s·hm2; q is calculated according to the relevant provisions of the current "Outdoor Drainage Design Code" GB50016-2006 (2014 edition).

[0065] In step S3, the construction of the regional sewage collection system includes the following method:

[0066] S301. Investigate the water system and existing ditches in the region, and make full use of the existing water system and ditches to build a sewage collection system;

[0067] S302. Conduct flood control and drainage analysis and, if necessary, construct flood control and drainage facilities to meet flood control and drainage requirements.

[0068] In step S4, the structural diagram of the automatic sewage storage and diversion system is as follows: Figure 2 , Figure 3 As shown in the figure, the automatic sewage storage and diversion system includes the following sequence: water inlet channel 1, overflow facility 2, slag interception facility 3, water inlet control facility 4 (with water level sensor controller), sedimentation tank 5, water storage tank 6 (with a capacity of 5600m 3 ), outlet control facilities 7 and outlet channel 8; slag intercepting facilities 3 intercept solid suspended matter entering the automatic storage and diversion system; sedimentation tank 5 precipitates and filters silt and pollutants attached to the silt; the sewage collected by the water storage tank 6, when the water volume reaches 5470 (the calculated initial rainwater volume), the water level sensor controller is used to automatically close the water inlet control facility 4, and the later rainwater flows out from the overflow facility 2 and merges into the ditch, channel or river at the source, so as to realize the effective separation of initial rainwater and later rainwater.

[0069] In step S5, the non-point source pollution natural purification system is designed and constructed to form a natural wetland according to the initial rainwater volume, inlet water quality and outlet water quality requirements, as well as wetland construction standards and specifications; the initial rainwater is collected and sent to the natural wetland for purification through the outlet channel 8 to obtain purified rainwater. The natural wetland area in this embodiment is 6500m 2, hydraulic load is 0.084m 3 / (m 2 ·d), hydraulic retention time is 5d.

[0070] The pollutant concentrations in the initial rainwater and the purified rainwater in this embodiment are listed in Table 2.

[0071] Table 2 Pollutant concentrations in rainwater before and after purification

[0072] Pollutants <![CDATA[COD CR ]]> <![CDATA[NH3-N]]> TP TN SS Initial rainfall (mg / L) 36 1.48 0.31 1.51 55 Purified rainwater (mg / L) 17 0.89 0.15 0.91 14 Pollutant removal rate (%) 52.8 39.9 51.61 39.7 74.5

[0073] From the data in Table 2, we can see that the water quality of non-point source pollution in the initial rainwater stage is Class V of the surface water quality classification. After purification, the water quality is improved to Class III of the surface water quality classification.

[0074] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for automatic collection and natural purification of surface pollution, characterized in that: The following steps are involved: Determine the initial rainwater volume in non-point source pollution according to formula 1; Among them, Q is the initial rainwater volume in non-point source pollution, unit is m 3 ; F is the catchment area of ​​non-point source pollution area, unit is hm2; is the runoff coefficient; T is the water collection time, in min; q is the rainstorm intensity, in L / s·hm2; Using the collection system to collect the initial rainwater to the storage and diversion system, the collected initial rainwater is obtained; The collected initial rainwater is purified by using a natural purification system to obtain purified rainwater.

2. The method for automatic collection and natural purification of non-point source pollution according to claim 1, characterized in that: The storage and diversion system comprises an inlet channel (1), an overflow facility (2), a slag blocking facility (3), an inlet control facility (4), a sedimentation tank (5), a water storage tank (6), an outlet control facility (7) and an outlet channel (8) which are connected in series in sequence.

3. The method for automatic collection and natural purification of non-point source pollution according to claim 2, characterized in that: The capacity of the water storage tank (6) is greater than or equal to the initial rainwater volume.

4. The method for automatic collection and natural purification of non-point source pollution according to any one of claims 1 to 3, characterized in that: The collection system includes the original water system and / or the original ditch in the area to be treated.

5. The method for automatic collection and natural purification of non-point source pollution according to claim 4, characterized in that: The original ditch includes a water diversion weir or a water diversion ditch.

6. The method for automatic collection and natural purification of non-point source pollution according to claim 1, characterized in that: The natural purification system includes natural wetlands or artificial wetlands.

7. The method for automatic collection and natural purification of non-point source pollution according to claim 1, characterized in that: The F is determined according to the distribution of non-point source pollution in the area to be treated.

8. The method for automatic collection and natural purification of non-point source pollution according to claim 1, characterized in that: Said Determined based on the topography and rainfall characteristics of the area to be treated.

9. The method for automatic collection and natural purification of non-point source pollution according to claim 1, characterized in that: The T is 15 min.

10. The method for automatic collection and natural purification of non-point source pollution according to claim 1, characterized in that: The q is calculated according to GB50016-2006.

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