Method for carrying out non-point source pollution treatment by utilizing river slope

Abstract

The invention belongs to the field of non-point source pollution abatement, and provides a method for conducting non-point source pollution abatement through a river slope. According to the method, at least two guide plates are arranged at a river slope where non-point source pollution wastewater flows into the river, the upper ends and the lower ends of the guide plates are connected with the top and the bottom of the slope respectively, and a non-point source pollution treatment area is formed between the guide plates; the method comprises the following steps: digging a plurality of discretely distributed filler pits on a slope surface of a non-point source pollution control area, fixing filler bags containing a carbon-based functional material or an environmental functional material in the filler pits, and enabling the filler bags to protrude out of the slope surface; non-point source pollution wastewater is introduced into the non-point source pollution treatment area or an oxidizing agent is added while the wastewater is introduced, and the wastewater makes contact with materials in the filler bag in the process of flowing through the non-point source pollution treatment area so as to achieve adsorption or adsorption and degradation of pollutants. An effective way is provided for treatment of non-point source pollution, and the threat of the non-point source pollution to the river ecological environment can be relieved.

Description

Technical Field

[0001] The invention belongs to the field of non-point source pollution control and relates to a method for controlling non-point source pollution by utilizing river slope. Background Art

[0002] Non-point source pollution mainly includes runoff from rural irrigation water, rural wastewater, and surface rainwater runoff. Direct discharge of non-point source pollution without effective treatment is one of the main reasons for the deterioration of the water environment of rivers and lakes. Due to the extensiveness and particularity of non-point source pollution, the amount of non-point source pollution water is extremely large. Treatment through traditional point source pollution control technologies such as sewage treatment plants faces many problems such as high cost, large land occupation, and operational difficulties. In addition, the types of pollutants in non-point source pollution are complex, including organic pollution, heavy metal pollution, nitrogen and phosphorus pollution, etc., and the concentration differences are large, which is difficult to remove through the self-purification function of the river. Some studies have attempted to control non-point source pollution through biological control methods such as plant absorption and microbial metabolism, but they still face problems such as low treatment efficiency and difficulty in effectively removing or even in removing some pollutants.

[0003] Although there is a potential possibility to remove pollutants from non-point source pollution by catalytic oxidation, reduction, adsorption and other methods using solid-phase materials, the treatment effect of solid-phase catalytic materials is poor due to factors such as difficulty in fixation and short hydraulic retention time. This technology still faces the problem of being difficult to apply in actual scenarios. Therefore, non-point source pollution still poses a serious threat to the river water quality environment, and more effective non-point source pollution control technologies are urgently needed.

[0004] The river slope is the inclined slope adjacent to the water surface on both sides of the river. It is an important hydraulic structure to ensure the normal function of the river. At present, the development of river slopes is still mainly to play its role in ensuring the water conservancy function of the river, and there is little research and development on the ecological management function of river slopes. As a necessary place for non-point source pollution to enter the river, if the river slope can be given the ability to manage non-point source pollution based on the structural design of the river slope and in combination with environmental functional materials, the pollutants in the non-point source pollution wastewater can be effectively removed when it flows through the river slope, which will have a positive significance for the management of non-point source pollution. Summary of the invention

[0005] In view of the problem that non-point source pollution currently poses a serious threat to the river ecological environment but there is no effective method to control it, the present invention provides a method for controlling non-point source pollution using river slopes, thereby providing an effective way to control non-point source pollution.

[0006] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is as follows:

[0007] The method for controlling non-point source pollution by using river slopes includes the following steps:

[0008] (1) Preparation of biochar-based functional materials

[0009] The biochar precursor is roasted at 200 to 1500° C. to obtain the biochar, the biochar, the non-metallic element precursor and the metal salt are fully mixed to obtain a reaction precursor, and the reaction precursor is roasted at 200 to 1500° C. to obtain the biochar-based functional material;

[0010] The non-metal element precursor is a compound containing at least one of fluorine, sulfur, oxygen, nitrogen and phosphorus, and the metal salt is at least one of iron salt, copper salt, cobalt salt and nickel salt;

[0011] (2) At least two guide plates shall be installed at the river bank where non-point source pollution wastewater flows into the river. The upper and lower ends of the guide plates shall be connected to the top and bottom of the slope respectively. The area between the guide plates shall be the non-point source pollution control area. The length of the guide plates shall be at least twice the distance between the top and bottom of the slope, and the distance between adjacent guide plates shall be 1 to 5 m.

[0012] A number of discretely distributed filling pits are dug on the slope of the non-point source pollution control area, the total area of ​​each filling pit on the slope accounts for 5% to 80% of the area of ​​the slope of the non-point source pollution control area, and the biochar-based functional material or environmental functional material is coated in a gauze with a micron-level pore structure to form a filling bag, and the filling bag is fixed in each filling pit so that the filling bag protrudes from the slope;

[0013] The environmental functional material is formed by fully mixing a biochar-based functional material and a solid oxidant, wherein the solid oxidant is a solid oxidant material that is insoluble in water or slightly soluble in water, or a water-soluble solid oxidant material loaded in a slow-release material;

[0014] (3) When the filler bag in step (2) does not contain a solid oxidant, a liquid oxidant is added to the non-point source pollution wastewater upstream of the non-point source pollution control area to form non-point source pollution wastewater containing oxidizing materials, wherein the liquid oxidant is a liquid oxidizing material, an aqueous solution of a liquid oxidizing material, or an aqueous solution of a solid oxidizing material; the non-point source pollution wastewater containing the oxidizing material is introduced into the non-point source pollution control area, and the wastewater contacts with the biochar-based functional material in the process of flowing through the non-point source pollution control area, and the biochar-based functional material and the oxidizing material degrade and adsorb the pollutants in the wastewater, thereby removing the pollutants in the wastewater, and achieving the control of the non-point source pollution wastewater;

[0015] Alternatively, when the filler bag in step (2) does not contain a solid oxidant, the non-point source pollution wastewater is introduced into the non-point source pollution control area, and the wastewater contacts with the biochar-based functional material in the process of flowing through the non-point source pollution control area, and the biochar-based functional material adsorbs the pollutants in the wastewater, removes the pollutants in the wastewater, and realizes the control of the non-point source pollution wastewater;

[0016] When the filler bag in step (2) contains a solid oxidant, the non-point source pollution wastewater is introduced into the non-point source pollution control area. The wastewater comes into contact with the environmental functional materials in the process of flowing through the non-point source pollution control area. The environmental functional materials degrade and adsorb the pollutants in the wastewater, remove the pollutants in the wastewater, and achieve the control of the non-point source pollution wastewater.

[0017] In the reaction precursors of step (1) of the above technical solution, the contents of biochar, non-metallic element precursor and metal salt are preferably 50wt% to 90wt%, 4wt% to 20wt% and 6wt% to 30wt%, respectively.

[0018] In step (1) of the above technical solution, the non-metallic element precursor is at least one of fluoride salts, sulfide salts, nitrates, ammonium salts, phosphates, pyrophosphates, oxalic acid, and thiocyanates.

[0019] In the above technical solution, the content of the solid oxidation material in the environmental functional material is preferably 5wt% to 30wt%.

[0020] In the above technical solution, when step (3) requires adding a liquid oxidant to the non-point source pollution wastewater upstream of the non-point source pollution control area to form non-point source pollution wastewater containing oxidizing materials, the amount of the liquid oxidant added is determined according to the type of oxidizing materials in the liquid oxidant and the type of pollutants to be degraded in the non-point source pollution wastewater. Generally, the concentration of oxidizing materials in the non-point source pollution wastewater containing oxidizing materials can be controlled to be 10 -7 wt%~1wt%. In practical applications, the specific concentration of the oxidizing material in the non-point source pollution wastewater can be determined through experiments based on the type of oxidizing material and the pollutants to be degraded.

[0021] In the above technical solution, the oxidizing material is calcium peroxide, persulfate, potassium permanganate, potassium dichromate, hydrogen peroxide or peracetic acid. Calcium peroxide is a solid oxidizing material that is slightly soluble in water. When used, it is directly mixed with a biochar-based functional material to form an environmental functional material. Persulfate, potassium permanganate, and potassium dichromate are water-soluble solid oxidizing materials. When used, they can be loaded into a slow-release material and then mixed with a biochar-based functional material to form an environmental functional material. They can also be dissolved in water to form a liquid oxidant and added to non-point source polluted wastewater. The slow-release material is a slow-release material commonly used in the prior art, including a degradable polymer material, an inorganic slow-release material, for example, paraffin, resin, sodium alginate, polymer-based, chitosan-based natural polymer material, starch-based natural polymer material, etc. Hydrogen peroxide and peracetic acid are liquid oxidizing materials. When used, hydrogen peroxide or peracetic acid is added as a liquid oxidant to the non-point source pollution wastewater, or an aqueous solution of hydrogen peroxide or an aqueous solution of peracetic acid is added as a liquid oxidant to the non-point source pollution wastewater. In the above technical scheme, when it is necessary to add a liquid oxidant to the non-point source pollution wastewater upstream of the non-point source pollution control area to form non-point source pollution wastewater containing oxidizing materials, the liquid oxidant can be slowly added in front of or at the entrance of the non-point source pollution control area through a pump or a dripping device.

[0022] In the above technical solution, the environmental functional material is composed of biochar-based functional materials and solid oxidants in the form of particles with a particle size in the micrometer or millimeter order.

[0023] In step (1) of the above technical solution, the biochar precursor includes but is not limited to animal carbon-containing products, plant carbon-containing products and carbon-containing wastes.

[0024] In step (1) of the above technical solution, biochar or biochar-based functional materials can be prepared by calcination in an atmosphere of air, oxygen, nitrogen, argon or a mixture of the above gases.

[0025] In step (1) of the above technical solution, when preparing biochar or biochar-based functional materials by roasting, it is preferred to control the roasting temperature to 400-1000° C. and the roasting time to 1-4 hours.

[0026] In the above technical scheme, the proportion of the total area of ​​the filling pits on the slope to the area of ​​the slope in the non-point source pollution control area is determined according to the water quality and flow rate of the wastewater to be polluted by the non-point source. If the concentration of pollutants in the wastewater is relatively high, the degradation of pollutants in the wastewater is relatively difficult, or the flow rate of the wastewater is relatively large, then the total area of ​​the filling pits on the slope should be increased as a proportion of the area of ​​the slope in the non-point source pollution control area.

[0027] In the above technical solution, the number of the filling pits is determined according to the area of ​​the non-point source pollution control area. The larger the area of ​​the non-point source pollution control area, the greater the number of filling pits. In practical applications, most basically, at least 5 filling pits are set in the non-point source pollution control area.

[0028] In the above technical solution, the filling pit array is distributed on the slope of the non-point source pollution control area. For example, the filling pits can be arranged in multiple rows and columns, and the filling pits can be staggered.

[0029] In the above technical solution, the main purpose of fixing the filler bag in each filler pit so that the filler bag protrudes from the slope is to increase the contact area between the wastewater and the filler bag on the one hand, and to increase the resistance to the flow of wastewater by using the part of the filler bag protruding from the slope on the other hand, thereby increasing the residence time of wastewater in the non-point source pollution control area. In practical applications, the height of the filler bag protruding from the slope can be determined according to the actual wastewater flow rate. When the wastewater flow rate is large, the height of the filler bag protruding from the slope can be increased. Generally speaking, the height of the filler bag protruding from the slope does not exceed the depth of the wastewater on the slope.

[0030] In step (2) of the above technical solution, the filling bags can be fixed in each filling pit by backfilling the gap between the filling bag and the filling pit with soil and gravel, or by driving fixing piles around the filling pit.

[0031] In order to avoid damage to the overall structure of the stuffing bag and its contents, in step (2) of the above technology, after the stuffing bag is fixed in each stuffing pit, a grille cover net can be set on the outside of the stuffing bag. Furthermore, in order to facilitate the replacement of a new stuffing bag after the service life of the stuffing bag contents has expired, the grille cover net is preferably fixed to the slope of the non-point source pollution control area in a detachable manner, or a stuffing bag replacement port is set on the grille cover net, and the stuffing bag replacement port can be opened and closed.

[0032] In the above technical solution, the guide plate is in a straight line, a broken line, a curved line, or a combination of two or more of the straight line, broken line and curved line. The structural form of the guide plate is mainly used to adjust the flow state and residence time of non-point source pollution wastewater in the non-point source pollution control area. In practical applications, a suitable guide plate structural form can be selected according to the water quality and flow rate of the non-point source pollution wastewater.

[0033] In the above technical scheme, in order to increase the uniformity of distribution of non-point source pollution wastewater in the non-point source pollution control area, especially when the distance between adjacent guide plates is large, for example, when the distance between adjacent guide plates exceeds 3m, a water distributor can be set at the entrance of the non-point source pollution control area.

[0034] Compared with the prior art, the technical solution provided by the present invention produces the following beneficial technical effects:

[0035] 1. The present invention provides a method for controlling non-point source pollution by using river slopes. The method transforms the river slopes so that the river slopes can play an ecological function while ensuring the water conservancy function of the river, thereby achieving the treatment of non-point source pollution wastewater flowing through the river slopes and realizing river ecological protection. Specifically, at least two guide plates are arranged at the river slope where non-point source pollution wastewater flows into the river, and the upper and lower ends of the guide plates are connected to the top and bottom of the slope respectively, so that a non-point source pollution control area is formed between the guide plates; then a number of discretely distributed filling pits are dug on the slope of the non-point source pollution control area, and the biochar-based functional material or the environmental functional material is coated in a gauze with a micron-level pore structure to form a filling bag, and the filling bag is fixed in each filling pit so that the filling bag protrudes from the slope; on this basis, by introducing non-point source pollution wastewater into the non-point source pollution control area or adding an oxidant while introducing the wastewater, the wastewater is contacted with the biochar-based functional material or the environmental functional material in the process of flowing through the non-point source pollution control area, and the biochar-based functional material or the environmental functional material adsorbs the pollutants in the wastewater or adsorbs and degrades them at the same time, so as to achieve the control of non-point source pollution wastewater. The present invention can solve the problem that non-point source pollution currently poses a serious threat to the ecological environment of rivers but there is no effective method for control, and provides an effective way for the control of non-point source pollution.

[0036] 2. The method described in the present invention can extend the length of the guide plate by selecting the structural form of the guide plate, for example, selecting a straight line type, a broken line type, a curved line type, or a combination of two or more of the straight line type, the broken line type and the curved line type, thereby extending the flow path of the non-point source pollution wastewater in the non-point source pollution control area, increasing the residence time of the wastewater in the non-point source pollution control area, and thereby increasing the total contact time of the wastewater with the environmental functional material or the biochar-based functional material, thereby effectively improving the adsorption and / or degradation efficiency of pollutants.

[0037] 3. During the preparation process of the biochar-based functional material used in the method of the present invention, non-metallic element doping can change the surface functional groups of the biochar-based functional material and improve its adsorption performance, and can change the electronic structure of the metal active center and improve the catalytic oxidation performance. The present invention uses the biochar-based functional material for adsorption or uses the biochar-based functional material as a key material in combination with an oxidant to oxidize and degrade the pollution source, which can improve the removal effect of pollutants.

[0038] 4. The present invention has been proved through experiments that the method of the present invention has excellent removal effect on organic pollutants in non-point source pollution wastewater. For example, after 1 μmol / L of atrazine simulated wastewater flows through the non-point source pollution control area, the removal rate of atrazine by the method of the present invention can reach 78.3% to 95.2%, and after 1 to 2 mg / L of ciprofloxacin simulated wastewater flows through the non-point source pollution control area, the removal rate of atrazine by the method of the present invention can reach 90.1% to 95.2%. The concentration of ciprofloxacin was calculated and the removal rate of ciprofloxacin was calculated. The results show that the removal rate of ciprofloxacin is 90.1% to 95.4%. At the same time, the method of the present invention can also effectively remove pollutants such as metal ions and nitrates in source pollution wastewater. The actual source pollution wastewater usually contains a variety of pollutants including organic pollutants and inorganic pollutants. It can be seen from the above experimental results that it is also feasible to use the method of the present invention for the treatment of actual non-point source pollution wastewater, and the method of the present invention is simple to operate and low in cost, which can effectively solve the high treatment cost and difficulty faced by non-point source pollution wastewater treatment in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of setting up a non-point source pollution control area on a river slope according to the present invention.

[0040] Figure 2 Another schematic diagram of setting up a non-point source pollution control area on a river slope according to the present invention.

[0041] Figure 3 This is another schematic diagram of setting up a non-point source pollution control area on a river slope according to the present invention.

[0042] In the figure, the red lines represent guide plates, the blue arrows represent the flow paths of non-point source pollution wastewater, and the gray circles represent the filler bags installed on the slopes in the non-point source pollution control area. DETAILED DESCRIPTION

[0043] The following examples further illustrate the method for controlling non-point source pollution by using river slopes of the present invention. It is necessary to point out that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. The technical personnel in the relevant field can make some non-essential improvements and adjustments to the present invention according to the above invention content and implement them specifically, which still falls within the scope of protection of the invention.

[0044] Example 1

[0045] In this embodiment, the method for controlling non-point source pollution by using river slopes according to the present invention is described in detail. Specifically, a simulated river slope is constructed in a laboratory to control non-point source pollution. The steps are as follows:

[0046] (1) Preparation of biochar-based functional materials

[0047] The straw is used as a precursor of biochar, and the straw is roasted at 500°C in an air atmosphere for 2 hours to obtain biochar. The biochar, sodium fluoride, ferric nitrate and copper nitrate are fully mixed to obtain a reaction precursor, in which the contents of biochar, sodium fluoride, ferric nitrate and copper nitrate are 50wt%, 25wt%, 12.5wt% and 12.5wt%, respectively. The reaction precursor is roasted at 500°C in an air atmosphere for 2 hours to obtain a biochar-based functional material, which is crushed and sieved to select a biochar-based functional material with a particle size between 20 and 50μm.

[0048] (2) Construction of simulated river slope

[0049] The size of the simulated river slope is determined according to the size of the actual river slope to be treated for non-point source pollution. The inclination angle of the actual river slope (the angle between the river slope surface and the horizontal plane) is 30°, and the height of the river slope (the vertical distance between the top and bottom of the river slope) is 6m. The ratio of the size of the simulated river slope to the size of the actual river slope is controlled to be 1:20. That is, the inclination angle of the simulated river slope is 30°, and the height of the simulated river slope is 0.3m.

[0050] (3) Set up a non-point source pollution control area on the simulated river slope

[0051] like Figure 1 As shown, two identical straight guide plates are set on the simulated river slope, the upper end and the lower end of the straight guide plate are connected to the top and the bottom of the slope respectively, the height direction of the straight guide plate is perpendicular to the slope surface, the angle between the length direction of the straight guide plate and the bottom of the slope (the boundary between the slope and the water surface) is 30°, the two straight guide plates are parallel to each other, the distance between the two straight guide plates is 0.3m, the length of the straight guide plate is 1.2m, and the height of the straight guide plate is 0.1m. The area between the two straight guide plates is the non-point source pollution control area, that is, in this embodiment, a parallelogram non-point source pollution control area is set on the simulated river slope.

[0052] Several discrete filling pits are dug on the slope of the non-point source pollution control area. The filling pits are evenly distributed on the slope. The outline of each filling pit on the slope is basically a circle with a diameter of 0.1m. The total area of ​​each filling pit on the slope accounts for 20% of the slope area of ​​the non-point source pollution control area. The environmental functional material is wrapped in a stainless steel mesh to form a filling bag, which is placed in each filling pit and fixed in the filling pit with soil and gravel. After fixation, the filling bag protrudes from the slope by about 2 to 5cm, and then a stainless steel grille cover is set on the outside of the filling bag, and the grille cover is fixed on the slope with cement to increase the fixing stability of the filling bag. The grille cover is provided with a replacement port that can be opened and closed to facilitate the replacement of the filling bag.

[0053] The pore size of the stainless steel mesh does not exceed 20 μm. The environmental functional material is formed by fully mixing the biochar-based functional material with a granular high molecular polymer sustained-release material loaded with sodium persulfate. The content of sodium persulfate in the environmental functional material is 10 wt%.

[0054] (4) Non-point source pollution control

[0055] Atrazine was dissolved in tap water to prepare a solution with an atrazine concentration of 1 μmol / L, and the solution was used as simulated wastewater. The simulated wastewater was continuously introduced into the non-point source pollution control area from the entrance of the non-point source pollution control area (the upper end of the non-point source pollution control area) at a flow rate of 5 mL / min. In the process of flowing through the non-point source pollution control area, the simulated wastewater came into contact with the environmental functional materials, and the environmental functional materials oxidized and degraded the pollutants in the simulated wastewater and adsorbed them, thereby removing the pollutants in the simulated wastewater.

[0056] When the flow rate of the simulated wastewater in the non-point source pollution control area reached a stable state, water samples were taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area) to test the atrazine concentration and calculate the atrazine removal rate. The results showed that the atrazine removal rate was 78.3%.

[0057] Example 2

[0058] In this embodiment, the method for controlling non-point source pollution by using river slopes according to the present invention is described in detail. Specifically, a simulated river slope is constructed in a laboratory to control non-point source pollution. The steps are as follows:

[0059] (1) Preparation of biochar-based functional materials

[0060] The straw is used as a precursor of biochar, and the straw is roasted at 500°C in an air atmosphere for 2 hours to obtain biochar. The biochar, sodium fluoride, ferric nitrate and copper nitrate are fully mixed to obtain a reaction precursor, in which the contents of biochar, sodium fluoride, ferric nitrate and copper nitrate are 50wt%, 25wt%, 12.5wt% and 12.5wt%, respectively. The reaction precursor is roasted at 500°C in an air atmosphere for 2 hours to obtain a biochar-based functional material, which is crushed and sieved to select a biochar-based functional material with a particle size between 20 and 50μm.

[0061] (2) Construction of simulated river slope

[0062] The size of the simulated river slope is determined according to the size of the actual river slope to be treated for non-point source pollution. The inclination angle of the actual river slope (the angle between the river slope surface and the horizontal plane) is 0°, and the height of the river slope (the vertical distance between the top and bottom of the river slope) is 6m. The ratio of the size of the simulated river slope to the size of the actual river slope is controlled to be 1:20. That is, the inclination angle of the simulated river slope is 30°, and the height of the simulated river slope is 0.3m.

[0063] (3) Set up a non-point source pollution control area on the simulated river slope

[0064] like Figure 2 As shown in the figure, two identical zigzag guide plates are set on the simulated river slope. The upper and lower ends of the zigzag guide plates are connected to the top and bottom of the slope respectively. The zigzag guide plates are composed of several bending sections. The length of each bending section is 40-50 cm. The angle between two adjacent bending sections is 30-60°. The height direction of the zigzag guide plate is perpendicular to the slope surface. The two zigzag guide plates are parallel to each other. The distance between the two zigzag guide plates is 0.3 m. The total length of the zigzag guide plates is 2.4 m. The height of the zigzag guide plates is 0.1 m. The area between the two zigzag guide plates is the non-point source pollution control area.

[0065] On the slope of the non-point source pollution control area, several discrete filling pits are dug, each filling pit is evenly distributed on the slope, and the outline of each filling pit on the slope is basically a circle with a diameter of 0.1m. The total area of ​​each filling pit on the slope accounts for 20% of the slope area of ​​the non-point source pollution control area. The environmental functional material is wrapped in a stainless steel mesh to form a filling bag, which is placed in each filling pit and fixed in the filling pit with soil and gravel. After fixing, the filling bag protrudes from the slope by about 2 to 5cm, and then a stainless steel grille cover is set on the outside of the filling bag, and the grille cover is fixed on the slope with cement to increase the fixing stability of the filling bag. The grille cover is provided with a replacement port that can be opened and closed to facilitate the replacement of the filling bag.

[0066] The pore size of the stainless steel mesh does not exceed 20 μm. The environmental functional material is formed by fully mixing the biochar-based functional material with a granular high molecular polymer sustained-release material loaded with sodium persulfate. The content of sodium persulfate in the environmental functional material is 10 wt%.

[0067] (4) Non-point source pollution control

[0068] Atrazine was dissolved in tap water to prepare a solution with an atrazine concentration of 1 μmol / L, and the solution was used as simulated wastewater. The simulated wastewater was continuously introduced into the non-point source pollution control area from the entrance of the non-point source pollution control area (the upper end of the non-point source pollution control area) at a flow rate of 5 mL / min. In the process of flowing through the non-point source pollution control area, the simulated wastewater came into contact with the environmental functional materials, and the environmental functional materials oxidized and degraded the pollutants in the simulated wastewater and adsorbed them, thereby removing the pollutants in the simulated wastewater.

[0069] When the flow rate of the simulated wastewater in the non-point source pollution control area reaches a stable state, a water sample is taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area), the concentration of atrazine is tested and the atrazine removal rate is calculated. The results show that the removal rate of atrazine is 95.2%. After running for one month, a water sample is taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area) for testing. The results show that the removal rate of atrazine is still maintained at a level of 90% to 95%. This shows that the method of the present invention has good long-term operation stability.

[0070] Comparative Example 1

[0071] The operation of this comparative example is basically the same as that of Example 2, except for the operation of step (3). The specific operation of step (3) of this example is as follows:

[0072] Two identical straight guide plates are set on the simulated river slope. The upper and lower ends of the straight guide plates are connected to the top and bottom of the slope respectively. The height direction of the straight guide plate is perpendicular to the slope surface. The angle between the length direction of the straight guide plate and the bottom (the boundary between the slope and the water surface) is 90°. The two straight guide plates are parallel to each other, the distance between the two straight guide plates is 0.3m, the length of the straight guide plate is 0.6m, and the height of the straight guide plate is 0.1m. The area between the two straight guide plates is the non-point source pollution control area.

[0073] On the slope of the non-point source pollution control area, several discrete filling pits are dug, each filling pit is evenly distributed on the slope, and the outline of each filling pit on the slope is basically a circle with a diameter of 0.1m. The total area of ​​each filling pit on the slope accounts for 20% of the slope area of ​​the non-point source pollution control area. The environmental functional material is wrapped in a stainless steel mesh to form a filling bag, which is placed in each filling pit and fixed in the filling pit with soil and gravel. After fixing, the filling bag protrudes from the slope by about 2 to 5cm, and then a stainless steel grille cover is set on the outside of the filling bag, and the grille cover is fixed on the slope with cement to increase the fixing stability of the filling bag. The grille cover is provided with a replacement port that can be opened and closed to facilitate the replacement of the filling bag.

[0074] The pore size of the stainless steel mesh does not exceed 20 μm. The environmental functional material is formed by fully mixing the biochar-based functional material with a granular high molecular polymer sustained-release material loaded with sodium persulfate. The content of sodium persulfate in the environmental functional material is 10 wt%.

[0075] In this comparative example, after the flow rate of the simulated wastewater in the non-point source pollution control area reached a stable state, water samples were taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area), the concentration of atrazine was tested and the atrazine removal rate was calculated. The results showed that the atrazine removal rate was 38.7%.

[0076] Combining Examples 1 to 2 and Comparative Example 1, it can be seen that as the length of the guide plate increases, the residence time of the simulated wastewater in the non-point source pollution control area increases, the total contact time between the simulated wastewater and the environmental functional materials increases, and the removal rate of atrazine is effectively improved. In practical applications, the removal effect of pollutants can be enhanced by extending the length of the guide plate.

[0077] Comparative Example 2

[0078] The operation of this comparative example is basically the same as that of Example 2, except for the operation of step (1). The specific operation of step (1) of this example is as follows:

[0079] The straw is used as a precursor of biochar, and the straw is roasted at 500°C in an air atmosphere for 2 hours to obtain biochar. The biochar, iron nitrate and copper nitrate are fully mixed to obtain a reaction precursor, in which the contents of biochar, iron nitrate and copper nitrate are 50wt%, 25wt% and 25wt%, respectively. The reaction precursor is roasted at 500°C in an air atmosphere for 2 hours to obtain a biochar-based functional material, which is crushed and sieved to select a biochar-based functional material with a particle size between 20 and 50μm.

[0080] In this comparative example, after the flow rate of the simulated wastewater in the non-point source pollution control area reached a stable state, water samples were taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area), the concentration of atrazine was tested and the atrazine removal rate was calculated. The results showed that the atrazine removal rate was 53.3%.

[0081] Combining Example 2 and Comparative Example 2, it can be seen that if the non-metallic element fluorine is not introduced for modification when preparing the biochar-based functional material, the removal effect of atrazine is poor when the prepared biochar-based functional material is used in combination with sodium persulfate. This is mainly due to the introduction of non-metallic element fluorine, which can change the surface functional groups of the biochar-based functional material and improve the adsorption performance on the one hand, and change the electronic structure of the metal active center on the other hand, and improve the catalytic oxidation performance of the biochar-based functional material.

[0082] Comparative Example 3

[0083] The operation of this comparative example is basically the same as that of Example 2, except that in this comparative example, the biocarbon-based functional material is directly used as the environmental functional material, that is, the environmental functional material does not contain sodium persulfate.

[0084] In this comparative example, after the flow rate of the simulated wastewater in the non-point source pollution control area reached a stable state, water samples were taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area), the concentration of atrazine was tested and the atrazine removal rate was calculated. The results showed that the atrazine removal rate was 20.6%.

[0085] Combining Example 2 and Comparative Example 3, it can be seen that the use of sodium persulfate in combination with biochar-based functional materials can significantly enhance the removal effect of atrazine, a difficult-to-degrade organic substance.

[0086] Example 3

[0087] In this embodiment, the method for controlling non-point source pollution by using river slopes according to the present invention is described in detail. Specifically, a simulated river slope is constructed in a laboratory to control non-point source pollution. The steps are as follows:

[0088] (1) Preparation of biochar-based functional materials

[0089] Pig manure was used as a precursor of biochar, and the pig manure was roasted at 400°C in an air atmosphere for 2 hours to obtain biochar. Biochar, thiocyanate and nickel nitrate were fully mixed to obtain a reaction precursor, in which the contents of biochar, thiocyanate and nickel nitrate were 83.4wt%, 8.3wt% and 8.3wt%, respectively. The reaction precursor was roasted at 1000°C in an air atmosphere for 1 hour to obtain a biochar-based functional material, which was crushed and sieved to select a biochar-based functional material with a particle size between 20 and 50μm.

[0090] (2) Construction of simulated river slope

[0091] The size of the simulated river slope is determined according to the size of the actual river slope to be treated for non-point source pollution. The inclination angle of the actual river slope (the angle between the river slope surface and the horizontal plane) is 30°, and the height of the river slope (the vertical distance between the top and bottom of the river slope) is 6m. The ratio of the size of the simulated river slope to the size of the actual river slope is controlled to be 1:20. That is, the inclination angle of the simulated river slope is 30°, and the height of the simulated river slope is 0.3m.

[0092] (3) Set up a non-point source pollution control area on the simulated river slope

[0093] like Figure 3 As shown in the figure, two identical curved guide plates are set on the simulated river slope, the upper and lower ends of the curved guide plates are connected to the top and bottom of the slope respectively, the height direction of the curved guide plates is perpendicular to the slope surface, the two curved guide plates are parallel to each other, the distance between the two curved guide plates is 0.3m, the total length of the curved guide plates is 2.6m, and the height of the curved guide plates is 0.1m. The area between the two curved guide plates is the non-point source pollution control area.

[0094] On the slope of the non-point source pollution control area, several discrete filling pits are dug, each filling pit is evenly distributed on the slope, and the outline of each filling pit on the slope is basically a circle with a diameter of 0.1m. The total area of ​​each filling pit on the slope accounts for 40% of the slope area of ​​the non-point source pollution control area. The environmental functional material is wrapped in a stainless steel mesh to form a filling bag, which is placed in each filling pit and fixed in the filling pit with soil and gravel. After fixing, the filling bag protrudes from the slope by about 2 to 5 cm.

[0095] The pore size of the stainless steel mesh does not exceed 20 μm. The environmental functional material is formed by fully mixing the biochar-based functional material and calcium peroxide particles. The content of the calcium peroxide particles in the environmental functional material is 20 wt%.

[0096] (4) Non-point source pollution control

[0097] Ciprofloxacin was dissolved in tap water to prepare a solution with a ciprofloxacin concentration of 1 mg / L, and the solution was used as simulated wastewater. The simulated wastewater was continuously introduced into the non-point source pollution control area from the entrance of the non-point source pollution control area (the upper end of the non-point source pollution control area) at a flow rate of 8 mL / min. During the process of flowing through the non-point source pollution control area, the simulated wastewater came into contact with the environmental functional materials, and the environmental functional materials oxidized and degraded the pollutants in the simulated wastewater and adsorbed them, thereby removing the pollutants in the simulated wastewater.

[0098] When the flow rate of the simulated wastewater in the non-point source pollution control area reaches a stable state, a water sample is taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area), the concentration of ciprofloxacin is tested and the ciprofloxacin removal rate is calculated, and the result shows that the removal rate of ciprofloxacin is 90.1%. After running for one month, a water sample is taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area) for testing, and the result shows that the removal rate of ciprofloxacin is still maintained at a level of 85% to 90%. This shows that the method of the present invention has good long-term operation stability.

[0099] Example 4

[0100] In this embodiment, the method for controlling non-point source pollution by using river slopes according to the present invention is described in detail. Specifically, a simulated river slope is constructed in a laboratory to control non-point source pollution. The steps are as follows:

[0101] (1) Preparation of biochar-based functional materials

[0102] Pig manure is used as a precursor of biochar, and the pig manure is roasted at 500°C in an air atmosphere for 2 hours to obtain biochar. The biochar, thiocyanate and nickel nitrate are fully mixed to obtain a reaction precursor, in which the contents of biochar, thiocyanate and cobalt nitrate are 50wt%, 20wt% and 30wt%, respectively. The reaction precursor is roasted at 1300°C in an air atmosphere for 1 hour to obtain a biochar-based functional material, which is crushed and sieved to select a biochar-based functional material with a particle size between 20 and 50μm.

[0103] (2) Construction of simulated river slope

[0104] The size of the simulated river slope is determined according to the size of the actual river slope to be treated for non-point source pollution. The inclination angle of the actual river slope (the angle between the river slope surface and the horizontal plane) is 30°, and the height of the river slope (the vertical distance between the top and bottom of the river slope) is 6m. The ratio of the size of the simulated river slope to the size of the actual river slope is controlled to be 1:20. That is, the inclination angle of the simulated river slope is 30°, and the height of the simulated river slope is 0.3m.

[0105] (3) Set up a non-point source pollution control area on the simulated river slope

[0106] like Figure 3As shown in the figure, two identical curved guide plates are set on the simulated river slope, the upper and lower ends of the curved guide plates are connected to the top and bottom of the slope respectively, the height direction of the curved guide plates is perpendicular to the slope surface, the two curved guide plates are parallel to each other, the distance between the two curved guide plates is 0.3m, the total length of the curved guide plates is 2.6m, and the height of the curved guide plates is 0.1m. The area between the two curved guide plates is the non-point source pollution control area.

[0107] On the slope of the non-point source pollution control area, several discrete filling pits are dug, each filling pit is evenly distributed on the slope, and the outline of each filling pit on the slope is basically a circle with a diameter of 0.1m. The total area of ​​each filling pit on the slope accounts for 40% of the slope area of ​​the non-point source pollution control area. The biochar-based functional material is wrapped in a stainless steel mesh to form a filling bag, which is placed in each filling pit and fixed in the filling pit with soil and gravel. After fixing, the filling bag protrudes from the slope by about 2 to 5 cm.

[0108] The pore size of the stainless steel mesh does not exceed 20 μm.

[0109] (4) Non-point source pollution control

[0110] Ciprofloxacin is dissolved in tap water to prepare a solution with a ciprofloxacin concentration of 2 mg / L, and the solution is used as simulated wastewater. Peracetic acid is added to the simulated wastewater until the concentration of the peracetic acid in the simulated wastewater is 0.05wt%. The simulated wastewater containing peracetic acid is continuously introduced into the non-point source pollution control area from the entrance of the non-point source pollution control area (the upper end of the non-point source pollution control area) at a flow rate of 5 mL / min. During the process of flowing through the non-point source pollution control area, the simulated wastewater contacts with the environmental functional material, and the environmental functional material oxidizes and degrades and adsorbs the pollutants in the simulated wastewater, thereby removing the pollutants in the simulated wastewater.

[0111] When the flow rate of the simulated wastewater in the non-point source pollution control area reaches a stable state, water samples are taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area) to test the concentration of ciprofloxacin and calculate the removal rate of ciprofloxacin. The results show that the removal rate of ciprofloxacin is 95.4%. After running for one month, water samples are taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area) for testing. The results show that the removal rate of ciprofloxacin is still maintained at a level of 90% to 95%.

[0112] Example 5

[0113] In this embodiment, the method for controlling non-point source pollution by using river slopes according to the present invention is described in detail. Specifically, a simulated river slope is constructed in a laboratory to control non-point source pollution. The steps are as follows:

[0114] (1) Preparation of biochar-based functional materials

[0115] Corn cobs were used as biochar precursors, and the corn cobs were roasted at 1000°C in an air atmosphere for 1 hour to obtain biochar. Biochar, oxalic acid and cobalt nitrate were fully mixed to obtain a reaction precursor, in which the contents of biochar, oxalic acid and cobalt nitrate were 87wt%, 8.7wt% and 4.3wt%, respectively. The reaction precursor was roasted at 400°C in an air atmosphere for 4 hours to obtain a biochar-based functional material, which was crushed and sieved to select a biochar-based functional material with a particle size between 20 and 50μm.

[0116] (2) Construction of simulated river slope

[0117] The size of the simulated river slope is determined according to the size of the actual river slope to be treated for non-point source pollution. The inclination angle of the actual river slope (the angle between the river slope surface and the horizontal plane) is 30°, and the height of the river slope (the vertical distance between the top and bottom of the river slope) is 6m. The ratio of the size of the simulated river slope to the size of the actual river slope is controlled to be 1:20. That is, the inclination angle of the simulated river slope is 30°, and the height of the simulated river slope is 0.3m.

[0118] (3) Set up a non-point source pollution control area on the simulated river slope

[0119] like Figure 2 As shown in the figure, two identical zigzag guide plates are set on the simulated river slope. The upper and lower ends of the zigzag guide plates are connected to the top and bottom of the slope respectively. The zigzag guide plates are composed of several bending sections. The length of each bending section is 40-50 cm. The angle between two adjacent bending sections is 30-60°. The height direction of the zigzag guide plate is perpendicular to the slope surface. The two zigzag guide plates are parallel to each other. The distance between the two zigzag guide plates is 0.3 m. The total length of the zigzag guide plates is 2.4 m. The height of the zigzag guide plates is 0.1 m. The area between the two zigzag guide plates is the non-point source pollution control area.

[0120] On the slope of the non-point source pollution control area, several discrete filling pits are dug, each filling pit is evenly distributed on the slope, and the outline of each filling pit on the slope is basically a circle with a diameter of 0.1m. The total area of ​​each filling pit on the slope accounts for 10% of the slope area of ​​the non-point source pollution control area. The environmental functional material is wrapped in a stainless steel mesh to form a filling bag, which is placed in each filling pit and fixed in the filling pit with soil and gravel. After fixing, the filling bag protrudes from the slope by about 2 to 5cm, and then a stainless steel grille cover is set on the outside of the filling bag, and the grille cover is fixed on the slope with cement to increase the fixing stability of the filling bag. The grille cover is provided with a replacement port that can be opened and closed to facilitate the replacement of the filling bag.

[0121] The pore size of the stainless steel mesh does not exceed 20 μm.

[0122] (4) Non-point source pollution control

[0123] A solution with a hexavalent chromium concentration of 5 mmol / L was used as simulated wastewater. The simulated wastewater was continuously introduced into the non-point source pollution control area from the entrance of the non-point source pollution control area (the upper end of the non-point source pollution control area) at a flow rate of 10 mL / min. In the process of flowing through the non-point source pollution control area, the simulated wastewater came into contact with the environmental functional materials, and the environmental functional materials reduced, degraded and adsorbed the pollutants in the simulated wastewater to remove the pollutants in the simulated wastewater.

[0124] When the flow rate of the simulated wastewater in the non-point source pollution control area reaches a stable state, water samples are taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area), the concentration of hexavalent chromium is tested and its removal rate is calculated. The results show that the removal rate of hexavalent chromium is 55.7%. It can be seen from this embodiment that for pollutants that do not require oxidative degradation, only biochar-based functional materials are added to the filler bag, and a satisfactory pollutant removal rate can also be achieved through the adsorption and reduction of the biochar-based functional materials.

[0125] Example 6

[0126] In this embodiment, the method for controlling non-point source pollution by using river slopes according to the present invention is described in detail. Specifically, a simulated river slope is constructed in a laboratory to control non-point source pollution. The steps are as follows:

[0127] (1) Preparation of biochar-based functional materials

[0128] Corn cobs were used as biochar precursors, and the corn cobs were roasted at 500°C in an air atmosphere for 2 hours to obtain biochar. Biochar, oxalic acid and cobalt nitrate were fully mixed to obtain a reaction precursor, in which the contents of biochar, oxalic acid and cobalt nitrate were 90wt%, 6wt% and 4wt%, respectively. The reaction precursor was roasted at 600°C in an air atmosphere for 2 hours to obtain a biochar-based functional material, which was crushed and sieved to select a biochar-based functional material with a particle size between 20 and 50μm.

[0129] (2) Construction of simulated river slope

[0130] The size of the simulated river slope is determined according to the size of the actual river slope to be treated for non-point source pollution. The inclination angle of the actual river slope (the angle between the river slope surface and the horizontal plane) is 30°, and the height of the river slope (the vertical distance between the top and bottom of the river slope) is 6m. The ratio of the size of the simulated river slope to the size of the actual river slope is controlled to be 1:20. That is, the inclination angle of the simulated river slope is 30°, and the height of the simulated river slope is 0.3m.

[0131] (3) Set up a non-point source pollution control area on the simulated river slope

[0132] like Figure 2 As shown in the figure, two identical zigzag guide plates are set on the simulated river slope. The upper and lower ends of the zigzag guide plates are connected to the top and bottom of the slope respectively. The zigzag guide plates are composed of several bending sections. The length of each bending section is 40-50 cm. The angle between two adjacent bending sections is 30-60°. The height direction of the zigzag guide plate is perpendicular to the slope surface. The two zigzag guide plates are parallel to each other. The distance between the two zigzag guide plates is 0.3 m. The total length of the zigzag guide plates is 2.4 m. The height of the zigzag guide plates is 0.1 m. The area between the two zigzag guide plates is the non-point source pollution control area.

[0133] On the slope of the non-point source pollution control area, several discretely distributed filling pits are dug, each filling pit is evenly distributed on the slope, and the outline of each filling pit on the slope is basically a circle with a diameter of 0.1m. The total area of ​​each filling pit on the slope accounts for 80% of the slope area of ​​the non-point source pollution control area. The biochar-based functional material is coated in a stainless steel mesh to form a filling bag, which is placed in each filling pit and fixed in the filling pit with soil and gravel. After fixation, the filling bag protrudes from the slope by about 2 to 5cm, and then a stainless steel grille cover is set on the outside of the filling bag, and the grille cover is fixed on the slope with cement to increase the fixing stability of the filling bag. The grille cover is provided with a replacement port that can be opened and closed to facilitate the replacement of the filling bag.

[0134] The pore size of the stainless steel mesh does not exceed 20 μm.

[0135] (4) Non-point source pollution control

[0136] Potassium nitrate and phenol were dissolved in tap water to prepare a solution with a potassium nitrate and phenol concentration of 8 mg / L and 1 mg / L, respectively, and the solution was used as simulated wastewater. The simulated wastewater was continuously introduced into the non-point source pollution control area from the entrance of the non-point source pollution control area (the upper end of the non-point source pollution control area) at a flow rate of 4 mL / min. During the process of flowing through the non-point source pollution control area, the simulated wastewater came into contact with the biochar-based functional material, and the biochar-based functional material adsorbed the pollutants in the simulated wastewater to remove the pollutants in the simulated wastewater.

[0137] When the flow rate of the simulated wastewater in the non-point source pollution control area reaches a stable state, water samples are taken from the outlet of the non-point source pollution control area (the lower end of the non-point source pollution control area), the concentrations of potassium nitrate and phenol are tested and the removal rates of the two are calculated. The results show that the removal rate of potassium nitrate is 31.3%, and the removal rate of phenol is 62.4%. It can be seen from this embodiment that for some pollutants, especially when the pollutant concentration is low, only adding biochar-based functional materials to the filler bag can also achieve a satisfactory pollutant removal rate through the adsorption of the biochar-based functional materials.

[0138] Those skilled in the art will appreciate that the embodiments described herein are intended to help technicians understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A method for controlling non-point source pollution by using river slopes, characterized in that: The following steps are involved: (1) Preparation of biochar-based functional materials The biochar precursor is roasted at 200 to 1500° C. to obtain the biochar, the biochar, the non-metallic element precursor and the metal salt are fully mixed to obtain a reaction precursor, and the reaction precursor is roasted at 200 to 1500° C. to obtain the biochar-based functional material; The non-metal element precursor is a compound containing at least one of fluorine, sulfur, oxygen, nitrogen and phosphorus, and the metal salt is at least one of iron salt, copper salt, cobalt salt and nickel salt; (2) At least two guide plates shall be installed at the river bank where non-point source pollution wastewater flows into the river. The upper and lower ends of the guide plates shall be connected to the top and bottom of the slope respectively. The area between the guide plates shall be the non-point source pollution control area. The length of the guide plates shall be at least twice the distance between the top and bottom of the slope, and the distance between adjacent guide plates shall be 1 to 5 m. A number of discretely distributed filling pits are dug on the slope of the non-point source pollution control area, the total area of ​​each filling pit on the slope accounts for 5% to 80% of the area of ​​the slope of the non-point source pollution control area, and the biochar-based functional material or environmental functional material is coated in a gauze with a micron-level pore structure to form a filling bag, and the filling bag is fixed in each filling pit so that the filling bag protrudes from the slope; The environmental functional material is formed by fully mixing a biochar-based functional material and a solid oxidant, wherein the solid oxidant is a solid oxidant material that is insoluble in water or slightly soluble in water, or a water-soluble solid oxidant material loaded in a slow-release material; (3) When the filler bag in step (2) does not contain a solid oxidant, a liquid oxidant is added to the non-point source pollution wastewater upstream of the non-point source pollution control area to form non-point source pollution wastewater containing oxidizing materials, wherein the liquid oxidant is a liquid oxidizing material, an aqueous solution of a liquid oxidizing material, or an aqueous solution of a solid oxidizing material; the non-point source pollution wastewater containing the oxidizing material is introduced into the non-point source pollution control area, and the wastewater contacts with the biochar-based functional material in the process of flowing through the non-point source pollution control area, and the biochar-based functional material and the oxidizing material degrade and adsorb the pollutants in the wastewater, thereby removing the pollutants in the wastewater, and achieving the control of the non-point source pollution wastewater; Alternatively, when the filler bag in step (2) does not contain a solid oxidant, the non-point source pollution wastewater is introduced into the non-point source pollution control area, and the wastewater contacts with the biochar-based functional material in the process of flowing through the non-point source pollution control area, and the biochar-based functional material adsorbs the pollutants in the wastewater, removes the pollutants in the wastewater, and realizes the control of the non-point source pollution wastewater; When the filler bag in step (2) contains a solid oxidant, the non-point source pollution wastewater is introduced into the non-point source pollution control area. The wastewater comes into contact with the environmental functional materials in the process of flowing through the non-point source pollution control area. The environmental functional materials degrade and adsorb the pollutants in the wastewater, remove the pollutants in the wastewater, and achieve the control of the non-point source pollution wastewater.

2. The method for controlling non-point source pollution by using river slope according to claim 1 is characterized in that: In the reaction precursor of step (1), the contents of biochar, non-metallic element precursor and metal salt are 50wt% to 90wt%, 4wt% to 20wt% and 6wt% to 30wt% respectively.

3. The method for controlling non-point source pollution by using river slope according to claim 1 is characterized in that: The non-metallic element precursor in step (1) is at least one of fluoride salts, sulfide salts, nitrates, ammonium salts, phosphates, pyrophosphates, oxalic acid, and thiocyanates.

4. The method for controlling non-point source pollution by using river slope according to claim 1 is characterized in that: The content of the solid oxidation material in the environmental functional material is 5wt% to 30wt%.

5. The method for controlling non-point source pollution by using river slope according to claim 1 is characterized in that: When step (3) requires adding a liquid oxidant to the surface source pollution wastewater upstream of the surface source pollution control area to form surface source pollution wastewater containing oxidizing materials, the concentration of oxidizing materials in the surface source pollution wastewater containing oxidizing materials is controlled to be 10 -7 wt%~1wt%.

6. The method for controlling non-point source pollution by using river slope according to any one of claims 1 to 5, characterized in that: The oxidizing material is calcium peroxide, persulfate, potassium permanganate, potassium dichromate, hydrogen peroxide or peracetic acid.

7. The method for controlling non-point source pollution by using river slope according to any one of claims 1 to 5, characterized in that: The filling pit array is distributed on the slope surface of the non-point source pollution control area.

8. The method for controlling non-point source pollution by using river slope according to any one of claims 1 to 5, characterized in that: After the stuffing packs are fixed in each stuffing pit, a grille cover is installed on the outside of the stuffing packs.

9. The method for controlling non-point source pollution by using river slope according to claim 8, characterized in that: The grille cover net is fixed on the slope surface of the non-point source pollution control area in a detachable manner, or a filling bag replacement port is set on the grille cover net, and the filling bag replacement port can be opened and closed.

10. The method for controlling non-point source pollution by using river slope according to any one of claims 1 to 5, characterized in that: The guide plate is in a straight line shape, a broken line shape, a curved line shape, or a combination of two or more of the straight line shape, the broken line shape and the curved line shape.

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