An embedded baffle purification device for field drainage and its use

Abstract

The present invention provides an embedded baffle purification device for field drainage and its use, the device comprising a primary purification unit and a main purification unit, the primary purification unit being connected to the main purification unit. The main purification unit is transversely embedded in the field ridge, does not occupy the farmland area, and a plurality of filler layers are arranged inside the unit. The device is provided with an upward-downward baffle path to increase the flow, and the filtration and adsorption of the multi-layer filler system can quickly remove suspended solids and nitrogen and phosphorus nutrients in paddy field drainage, thereby achieving the purpose of reducing the non-point source pollution load of paddy fields.

Description

Technical Field

[0001] The invention relates to a water purification device in the agricultural field, in particular to an embedded baffle purification device for field drainage and a use thereof. Background Art

[0002] As point source pollution such as industrial wastewater and urban domestic sewage in my country has been effectively controlled, agricultural non-point source pollution has become the most important source of water environmental pollutants. The second national pollution source census bulletin shows that total nitrogen and total phosphorus emitted from agricultural sources account for 46.5% and 67.2% of the total water pollution emissions in the country, of which 51% and 36% come from the planting industry. The irrigation water consumption of rice production accounts for about 70% of the total agricultural water consumption, and the pollutants contained in rice field drainage have become the main source of agricultural non-point source pollution in the southern water network area. In the process of rice production, excessive application of chemical fertilizers and overloaded straw return to the field can easily lead to pollutants (solid suspended matter, nitrogen and phosphorus nutrients) entering the surrounding water bodies through runoff drainage, which is one of the important reasons for eutrophication of water bodies and deterioration of water quality. At the same time, large-scale irrigation and abundant rainfall will also lead to an increase in the environmental load of pollutants such as nitrogen and phosphorus discharged through runoff. In particular, the annual rainfall in the rice planting area of ​​the middle and lower reaches of the Yangtze River is concentrated in the rice season, and there are frequent heavy rainfall weather, which can easily lead to solid suspended matter such as soil clay particles, nitrogen and phosphorus and other pollutants entering the water body through runoff drainage, thereby increasing the risk of water pollution.

[0003] At present, the main method for rice field drainage treatment in China is to use ecological ditch interception technology. This technology is to intercept and purify rice field drainage when it flows through the ecological ditch by building new drainage ditches or carrying out ecological transformation of existing drainage ditches. The purification principle of existing ecological ditch technology is basically similar. The main problem is that most ecological ditches have poor impact load resistance and cannot meet the requirements of rapid treatment when instantaneous large flow and high pollutant concentration are high. In addition, ecological ditches are usually long, which not only requires a large amount of transformation work, but also requires the planting of aquatic plants on the ditch wall or ditch bottom, and the subsequent maintenance cost is high. If the maintenance is not done properly, the plants will be too lush and affect the smooth drainage of rice fields, which affects the large-scale promotion of ecological ditches.

[0004] There are not many inventions involving the use of rice field drainage outlets or ridges to control the water quality of rice field drainage. The ridges of rice fields are an important part of traditional rice fields, and their main function is to maintain the water layer in the field. The basic principles of high-standard farmland construction in my country include "square fields, network of channels, drainage of waterlogging, and no pollution", but so far, in addition to the technology of transforming drainage ditches into ecological purification ditches, the rice field system still lacks purification technology that can be seamlessly connected with the drainage ditch system of high-standard farmland construction, especially rice field drainage purification technology and equipment that utilizes the spatial structure of ridges, does not occupy farmland area, and does not affect ditch drainage. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide an embedded baffle purification device for field drainage, which is used to solve the problems in the prior art that the device occupies a large area of ​​farmland and is difficult to purify rice field drainage.

[0006] To achieve the above-mentioned object and other related objects, the present invention provides an embedded baffle purification device for field drainage, the device comprising a primary purification unit and a main purification unit, the primary purification unit being connected to the main purification unit;

[0007] The primary purification unit is filled with primary purification material; a water inlet is provided between the primary purification unit and the main purification unit, and the valve of the water inlet is a gate with adjustable height;

[0008] The main purification unit includes a number of purification treatment modules which are fluidically connected in sequence, and the connection positions between each purification treatment module and two adjacent purification treatment modules are respectively located at the top and bottom of the purification treatment module, so that water flows through each purification treatment module from top to bottom or from bottom to top; a packing layer is arranged inside each purification treatment module, and the packing layer includes a top layer packing, a middle layer packing and a bottom layer packing, the top layer packing and the bottom layer packing are porous packing layers, and the middle layer packing is an adsorptive packing layer.

[0009] Furthermore, the primary purification material is natural zeolite.

[0010] Furthermore, the gate includes a plurality of detachable gate plates, and the water inlet can be closed when all the gate plates are in use.

[0011] Furthermore, the filler in the porous filler layer is selected from any one or more of porous glass pumice, volcanic rock, vermiculite, or artificial ceramsite; and the adsorptive filler layer is selected from any one or two of natural zeolite or biochar.

[0012] Furthermore, the filler layer includes a first porous glass pumice layer, a natural zeolite layer and a second porous glass pumice layer which are sequentially arranged from bottom to top.

[0013] Furthermore, the first porous glass pumice layer contains plastic hollow balls.

[0014] Furthermore, the main purification unit is a box structure as a whole, and a plurality of water retaining plates are arranged inside the box to divide the entire box into a plurality of purification processing modules.

[0015] Furthermore, a porous water distribution plate is provided between the top layer filler and the middle layer filler in the purification treatment module connected to the water inlet.

[0016] Furthermore, each purification treatment module is fluidically connected to two adjacent purification treatment units through the notch on the top of the water retaining plate and the porous water collecting pipe at the bottom.

[0017] Another aspect of the present invention provides use of the above purification device for purifying field sewage.

[0018] As described above, the field drainage purification device of the present invention has the following beneficial effects:

[0019] Without occupying farmland area and without affecting ditch drainage, the available space on the rice field structure is fully utilized, the treatment device is horizontally embedded inside the field ridge, and the flow is increased by setting an upward-downward flow path inside the device. Combined with the filtration and adsorption of the multi-layer filler system, the solid suspended matter and nitrogen and phosphorus nutrients in the rice field drainage can be quickly removed, thereby achieving the purpose of reducing the non-point source pollution load of the rice field. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Shown is a perspective view of the present purification device;

[0021] Figure 2 The display is the installation cross-section diagram of the purification device;

[0022] Figure 3 Shown is a schematic diagram of a segmented water inlet of the purification device;

[0023] Figure 4 Shown is a cross-sectional view of the packing of this purification device.

[0024] Component number description

[0025] 1 Primary purification unit

[0026] 2 water inlet

[0027] 3. The first porous water collecting pipe

[0028] 4 Second porous water collecting pipe

[0029] 5. First water barrier

[0030] 6 Second water barrier

[0031] 7 Third water retaining plate

[0032] 8 Fourth water barrier

[0033] 9 Drain pipe

[0034] 10 Top cover

[0035] 11 Water distribution board

[0036] 12 Top filler

[0037] 13. Intermediate layer filler

[0038] 14 Underfill

[0039] 15 Card slot

[0040] 16 Top gate

[0041] 17 Intermediate gate

[0042] 18 Lower gate

[0043] 19 Rice Field

[0044] 20 Drainage ditch DETAILED DESCRIPTION

[0045] The following is a description of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0046] See also Figures 1 to 4 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0047] Example: Rice fields in a village in Fengxian District, Shanghai. The experimental rice field covers an area of ​​5 mu, planted with conventional rice, and fertilized and irrigated according to the conventional management. Drainage of rice fields mainly occurs during heavy rainfall and during the drainage period of rice fields. Water samples are collected at the inlet and outlet of the device and tested for suspended solids, total nitrogen and total phosphorus.

[0048] like Figure 1-4 As shown, the device is mainly used to purify drainage in the field. When the purification device is installed, the main structure is embedded in the ridge of the rice field 19 near the drainage ditch 20, and the top of the device is flush with the top surface of the ridge.

[0049] The purification device includes a primary purification unit 1 and a main purification unit, wherein the primary purification unit is connected to the main purification unit so that water flows from the primary purification unit into the main purification unit. A water inlet 2 is arranged on the upper part of the main purification unit, and the primary purification unit 1 is arranged around the water inlet 2. The primary purification unit is small in size and is located at the top of the side of the main purification unit.

[0050] The primary purification unit is filled with primary purification material; the valve of the water inlet is a gate with adjustable height. The primary purification unit includes a primary purification box and a primary purification material arranged in the box. The primary purification material can be natural zeolite. The primary purification box adopts a water distribution plate with a porous structure. The primary purification device mainly prevents large suspended matter from entering.

[0051] In a preferred embodiment, the gate includes a plurality of detachable gate plates, and the water inlet can be closed when all the gate plates are in use. For example, in this embodiment, three gate plates are provided, namely, the top gate plate 16, the middle gate plate 17 and the lower gate plate 18 (all 10 cm high and 30 cm wide). A card slot 15 is provided at the water inlet, and the three gate plates can be inserted into the card slot. The user can change the height of the gate plate at the water inlet according to the water demand in the field. The junction between the middle gate plate and the lower gate plate is flush with the surface of the paddy field soil. When the field needs to store water, all three gate plates are inserted into the water inlet card slot. When rice is flooded, two gate plates (the middle gate plate and the lower gate plate) are generally inserted, which can store 10 cm deep field surface water; if the water level rises due to heavy rainfall, it can overflow into the device through the top of the gate plate; when the field surface water of the paddy field needs to be discharged, only the top gate plate is left, and when deep drainage is required, all gate plates are removed. Overflow water from rice field drainage or heavy rainfall enters the device through the primary filtration system.

[0052] The main purification unit includes a number of purification treatment modules that are fluidically connected in sequence. The connection positions between each purification treatment module and the adjacent purification treatment modules are respectively located at the top and bottom of the purification treatment module, so that water flows from top to bottom or from bottom to top when passing through each purification treatment module; each purification treatment module is internally provided with a packing layer, and the packing layer includes a top and bottom porous packing layer, and an adsorbent packing layer in the middle. The main function of the porous packing is to intercept larger particle pollutants, and the function of the adsorbent packing is to adsorb ammonia nitrogen and phosphorus. Of course, some porous packings also have adsorption effects, and some adsorbent packings can also intercept larger particle pollutants.

[0053] In a preferred embodiment, the filler in the porous filler layer is selected from any one or more of porous glass pumice, volcanic rock, vermiculite, or artificial ceramsite. The adsorbent filler is selected from any one or two of natural zeolite or biomass charcoal. The purpose of the filler is mainly to further purify the water quality, so any particles with adsorption function that can achieve the effect of purifying the water quality can be used as fillers.

[0054] In a preferred embodiment, the filler layer includes a first porous glass light stone layer (4-6cm in diameter) arranged in sequence from bottom to top, with a filling depth of about 30cm, a natural zeolite layer (3-5cm in diameter), the zeolite filler is stacked and laid after being filled in a mesh bag, with a filling depth of 40cm, and a second porous glass light stone layer. The main component of the natural zeolite filler is aluminosilicate, with excess negative charge, and there are cavities and channels with a certain aperture in the zeolite framework, which has a strong selective adsorption capacity for ammonia nitrogen and phosphorus, and can further reduce the nitrogen and phosphorus concentration in the drainage; the porous glass light stone filler has many pores, which not only increases the water capacity of the device, but also helps to further increase the retention time of the water flow, and the porous glass light stone has a large specific surface area, and microbial communities are easily formed in the pores, which can partially degrade the organic components in the drainage and extend the service life and action time of the filler. Therefore, the present invention reduces the non-point source pollution load of paddy field drainage by changing the water flow path and reasonably configuring the filler types, so that the suspended particles and pollutants such as nitrogen and phosphorus in the drainage are efficiently intercepted, settled and removed.

[0055] In a preferred embodiment, a porous water distribution plate is provided between the top layer filler and the middle layer filler in the purification treatment module connected to the primary purification unit.

[0056] In a preferred embodiment, the first porous glass pumice layer contains plastic hollow balls (2-3 cm in diameter). The hollow balls can increase the water holding volume and further increase the retention time of the water flow.

[0057] In a preferred embodiment, the main purification unit is a box structure as a whole, the top surface of the box is open, and a plurality of water retaining plates are arranged inside the box to divide the entire box into a plurality of purification processing modules. Figure 1 As shown, a first water baffle 5, a second water baffle 6, a third water baffle 7 and a fourth water baffle 8 are provided in the device.

[0058] In a preferred embodiment, each purification module is fluidically connected to two adjacent purification units through the notch at the top of the partition and the porous water collection pipe at the bottom. Figure 1 As shown, the device is provided with a first porous water collecting pipe 3 and a second porous water collecting pipe 4. Finally, the water flows into the drainage ditch 20 through the drainage pipe 9.

[0059] In a preferred embodiment, a top cover 10 is provided on the top of the main purification unit, and the provision of the top cover can prevent the entry of debris.

[0060] Each module is 100cm long, 40-50cm wide, and 70-90cm deep. The main structure can be made of hard plastic, PVC board or cement prefabricated board. At least 3 modules are connected for use. The corresponding number of modules can be connected according to the area of ​​the rice field (in principle, 1 module corresponds to the drainage of 1 mu of rice field. The more modules, the greater the magnification effect of the treatment area). The commonly used standard specification is 5 modules connected into a rectangular shape (attached Figure 1 ), can purify the drainage of 4-6 acres of rice fields.

[0061] When the rice fields are drained, the primary purification unit at the water inlet can remove larger impurities and suspended solids, and then the drainage enters the main purification unit to further intercept and purify pollutants. The water flow is uniformly infiltrated through the water distribution plate at the water inlet inside the device. The spatial structure design between the modules enables the water flow to achieve a downward-upward-downward baffle flow, which promotes the sedimentation of solid suspended solids in the drainage in the device, and promotes the full contact between pollutants in the drainage and the filler by increasing the retention time of the drainage on the migration path. The fillers with different spatial layouts in the device play a coordinated purification function. The adsorbent filler (natural zeolite) in the middle layer has a good adsorption effect on ammonia nitrogen and phosphorus, which can further reduce the nitrogen and phosphorus concentration in the drainage; the porous glass light stone filler surface of the bottom layer is easy to form a microbial community, which can partially degrade the organic components in the drainage, prevent blockage, and extend the service life and action time of the filler.

[0062] After purification, the purification rates of suspended solids, nitrogen and phosphorus in the drainage reached 50-80%, 30-60% and 30-60% respectively, and the treatment efficiency and operation indexes reached the design requirements. After being intercepted, adsorbed and purified by the purification device of the present invention, the paddy field drainage is finally collected into the field drainage ditch.

[0063] Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

[0064] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. An embedded baffle purification device for field drainage, characterized in that: The device at least comprises: The purification device is used to purify drainage in the field. When the purification device is installed, the main structure is embedded in the ridge of the rice field near the drainage ditch, and the top of the device is flush with the top surface of the ridge; the drainage from the rice field is intercepted, adsorbed and purified by the purification device, and finally flows into the field drainage ditch; A primary purification unit and a main purification unit, wherein the primary purification unit is connected to the main purification unit; The primary purification unit is filled with primary purification materials; a water inlet is provided between the primary purification unit and the main purification unit, and the valve of the water inlet is a gate with adjustable height; the gate includes a plurality of detachable gate plates, and the water inlet can be closed when all the gate plates are in use, and the gate includes three gate plates, namely a top gate plate, a middle gate plate and a lower gate plate, and a card slot is provided at the water inlet, and the three gate plates can be inserted into the card slot, and the junction of the middle gate plate and the lower gate plate is flush with the surface of the paddy field soil; the main purification unit is a box structure as a whole, and the top surface of the box is open; The main purification unit includes a number of purification treatment modules which are fluidically connected in sequence, and the connection positions between each purification treatment module and two adjacent purification treatment modules are respectively located at the top and bottom of the purification treatment module, so that water flows through each purification treatment module from top to bottom or from bottom to top; a packing layer is arranged inside each purification treatment module, and the packing layer includes a top layer packing, a middle layer packing and a bottom layer packing, the top layer packing and the bottom layer packing are porous packing layers, and the middle layer packing is an adsorptive packing layer.

2. The purification device according to claim 1, characterized in that: The primary purification material is natural zeolite.

3. The purification device according to claim 1, characterized in that: The porous filler layer is selected from any one or more of porous glass pumice, volcanic rock, vermiculite, or artificial ceramsite, and the adsorptive filler layer is selected from any one or two of natural zeolite or biomass charcoal.

4. The purification device according to claim 1, characterized in that: The filler layer comprises a first porous glass pumice layer, a natural zeolite layer and a second porous glass pumice layer which are sequentially arranged from bottom to top.

5. The purification device according to claim 4, characterized in that: The first porous glass pumice layer contains plastic hollow spheres.

6. The purification device according to claim 1, characterized in that: The main purification unit is a box structure as a whole, and a plurality of water retaining plates are arranged inside the box to divide the entire box into a plurality of purification processing modules.

7. The purification device according to claim 1, characterized in that: Each purification treatment module is fluidically connected to two adjacent purification treatment units through the notch on the top of the water retaining plate and the porous water collecting pipe at the bottom.

8. The purification device according to claim 7, characterized in that: A porous water distribution plate is arranged between the top layer filler and the middle layer filler in the purification treatment module connected to the water inlet.

9. Use of the purification device according to any one of claims 1 to 8 for purifying field drainage.

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