Long-life dust screen and dust suppression method thereof

Abstract

The application discloses a long-life dust screen and a dust suppression method thereof, and belongs to the technical field of environmental protection, which comprises a dust screen body and a surface treatment layer, wherein the surface treatment layer is a calcium carbonate deposition layer and uniformly covers the surface of the dust screen body. In the application, the physical strength and chemical stability of the dust screen are enhanced by forming a protective layer outside the dust screen body, the dust screen is prevented from being blown up by being bonded to the soil body through calcium carbonate deposition, the ability of the dust screen to resist adverse environmental conditions is improved, the dust suppression effect is improved, the grid structure of the dust screen can be maintained stable under extreme environments such as strong wind, high temperature and ultraviolet radiation, the dust screen is not prone to deformation and damage, thus the bare soil particles are effectively prevented from being blown up by the wind, the dust screen body can still maintain high filtration performance in long-term use, the service life of the dust screen is further prolonged, the replacement frequency caused by material aging is reduced, the maintenance cost is reduced, and the influence of the discarded dust screen on the environment is reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of environmental protection, and particularly relates to a long-life dust screen and a dust suppression method thereof. BACKGROUND

[0002] The existing dust screen often shows material aging phenomenon when exposed to harsh environmental conditions for a long time, such as wind, sunlight, rain, etc. This aging is manifested in the decrease of strength and toughness of the screen material, deformation and damage of the grid, thereby leading to the decrease of the filtration efficiency of the dust screen and the obvious weakening of the dust suppression effect. Specifically, the aged dust screen may not effectively intercept fine particulate matter, which exacerbates the dust problem, not only affecting the surrounding environmental quality, but also possibly causing harm to human health.

[0003] The effectiveness of the EICP solidification soil technology mainly depends on the effective cementation of calcium carbonate crystals between soil particles. After treatment with the EICP solution, the soil particles are cemented by calcium carbonate, forming complete soil blocks from the originally loose soil particles, and the crystal connection between the particles can significantly improve the mechanical properties of the treated soil sample;

[0004] Although there are various dust screen materials and dust suppression methods in the prior art, they generally have certain limitations. For example, some dust screens have good initial dust suppression effect, but after a period of use, their dust suppression effect will gradually decrease due to insufficient weather resistance of the material itself. At the same time, these technologies often only focus on improving one aspect of dust suppression effect or service life, lacking a comprehensive solution. This means that in the pursuit of higher dust suppression effect, the service life of the dust screen may be sacrificed, and vice versa;

[0005] Therefore, there is an urgent need in the market for an innovative technology that can overcome the shortcomings of existing technologies, significantly improve the dust suppression effect of the dust screen, and effectively extend its service life. Such a technology should be able to enhance the durability of the dust screen in some way while maintaining or improving its filtration performance, thereby ensuring environmental cleanliness while reducing the economic burden and resource waste caused by frequent replacement of the dust screen.

[0006] Based on this, the present application designs a long-life dust screen and a dust suppression method thereof to solve the above problems. SUMMARY

[0007] The present application aims to solve the problems of low service life and poor dust suppression effect of the dust screen, and proposes a long-life dust screen and a dust suppression method thereof.

[0008] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0009] The dustproof net has a long service life and is characterized in that it comprises a dustproof net body and a surface treatment layer, the surface treatment layer is a calcium carbonate precipitation layer and uniformly covers the surface of the dustproof net to form a firm protective layer, and the dustproof net body is directly laid on the surface of the soil and bonded to the soil through the calcium carbonate precipitation layer.

[0010] The base material of the dustproof net body can be polyester, polypropylene, nylon or other synthetic fibers.

[0011] As a further description of the above technical solution:

[0012] The calcium carbonate precipitation layer is formed by the urease hydrolysis reaction of the EICP solution to generate calcium carbonate precipitation and adhere to the surface of the dustproof net and the contact points between the dustproof net and the soil.

[0013] As a further description of the above technical solution:

[0014] The preparation method of the EICP solution is as follows: S1, selecting raw materials, selecting soybeans as the source of urease; the calcium source can be calcium chloride (CaCl2), calcium acetate (C4H6CaO4) or other calcium-containing compounds; and urea (CO(NH2)2) is selected as the carbon source;

[0015] S2, preparing a pulverizer to pulverize soybeans to extract urease, preparing a mixing container to contain raw materials and solutions, and then using a stirrer to ensure uniform mixing of the solution;

[0016] S3, a. extracting urease: put soybeans into a pulverizer to pulverize them into powder, then mix them with 10 times the amount of water by stirring, filter out the soybean residue after standing for a period of time, and obtain a urease solution;

[0017] b. dissolving calcium salt: add an appropriate amount of water to the mixing container, slowly add calcium salt, and continuously stir using a stirrer until the calcium salt is completely dissolved in water;

[0018] c. adding carbon source: add urea as a carbon source to the calcium salt solution, continue to stir the solution to ensure that the urea is completely dissolved, and the concentration ratio of calcium salt to urea is 1:1;

[0019] d. preparing EICP solution: add an equal volume of urease solution to the calcium salt and urea mixture, and then mix thoroughly;

[0020] S4, safety measures, during the entire preparation process, the operator should wear protective glasses, gloves and laboratory coats, and should ensure that the operation is carried out in good ventilation conditions.

[0021] As a further description of the above technical solution:

[0022] The spraying device is an adjustable watering can, which can control the spraying intensity and range to ensure that the solution can be uniformly sprayed.

[0023] As a further description of the above technical solution:

[0024] The main control factors of the construction process are: spraying volume, spraying sequence and reaction time, etc.

[0025] As a further description of the above technical solution:

[0026] The spraying volume: the reasonable spraying volume of dust suppressant in sandy soil is 3.66-4.00 L / m 2 Because the silt particle size is smaller than that of sandy soil, it is necessary to verify the applicable spraying volume under the condition of silt in Zhengzhou;

[0027] The spraying sequence: calcium carbonate is contained in the EICP reaction product, and the aggregation of calcium carbonate between soil particles will reduce the porosity of the soil body, thereby preventing the penetration and diffusion of the solution in the soil body. Therefore, the mixing and spraying sequence of the components in the EICP dust suppressant solution will determine the reaction curing effect;

[0028] The reaction time: as the EICP reaction time increases, urea is continuously decomposed to produce and combine with Ca 2+ in the solution to generate more calcium carbonate. As the calcium carbonate content continuously increases, the surface strength and the thickness of the cured layer of the sample will also increase. To explore the relationship between the curing effect of the dust suppressant after spraying and the action time, the influence of the reaction time on the curing effect of the EICP dust suppressant is analyzed.

[0029] As a further description of the above technical solution:

[0030] To explore the effect of different volumes of EICP solution on the reinforcement of silt, the surface compressive strength and thickness of the cured layer of the prepared soil sample under different spraying volumes need to be measured.

[0031] As a further description of the above technical solution:

[0032] The relationship between the thickness of the cured layer and the surface compressive strength is analyzed, and it is found that as the thickness of the cured layer increases, the surface compressive strength also increases, and there is a linear relationship between them. The linear relationship curve between the thickness of the cured layer and the compressive strength is as follows:

[0033] y = 78.3499x - 66.1416 (R 2 = 0.938) (4.2)

[0034] In the formula: y is the surface compressive strength, kPa;

[0035] x is the thickness of the cured layer, mm.

[0036] The coupling function variance is 0.938, all the measured values are located in the 95% confidence interval of the function, and therefore it can be considered that the surface compressive strength and thickness of the silt solidification layer in actual construction follow the function relationship.

[0037] The long-life dust screen dust suppression method comprises the following steps:

[0038] S1, using clean water and neutral cleaner to thoroughly clean the dust screen, remove the surface dust, oil stains and other impurities;

[0039] S2, after cleaning, check whether the dust screen is damaged or deformed, ensure that the net surface is complete and has no defects affecting the treatment effect;

[0040] S3, according to the material and on-site environmental conditions of the dust screen, prepare EICP solution with appropriate concentration and viscosity.

[0041] S4, using professional spraying equipment such as high-pressure spray gun, evenly spraying EICP solution on the dust screen, ensuring that each part can fully contact the solution;

[0042] S5, EICP solution reacts chemically and gradually forms calcium carbonate precipitate on the surface of the dust screen and between the dust screen and the soil particles.

[0043] As described above, by adopting the technical scheme, the present application has the following advantages:

[0044] In the present application, the physical strength and chemical stability of the dust screen are enhanced by forming a protective layer outside the dust screen body, and the dust screen is bonded to the soil body through calcium carbonate precipitation to prevent the dust screen from being blown up, which not only improves its ability to resist harsh environmental conditions, but also improves the dust suppression effect, and can maintain a stable grid structure in extreme environments such as strong wind, high temperature and ultraviolet radiation, and is not easy to deform and break, thereby effectively preventing bare soil particles from being blown up by the wind, so that the dust screen body can still maintain high filtration performance in long-term use, further prolonging the service life of the dust screen, reducing the replacement frequency due to material aging, reducing maintenance costs, and reducing the impact of discarded dust screens on the environment. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 A long-life dust screen and its dust suppression method are provided.

[0046] Figure 2 A long-life dust screen and its dust suppression method are provided.

[0047] Figure 3A broken line diagram of spraying volume and compressive strength of a long-life dust screen and dust suppression method thereof according to the present application;

[0048] Figure 4 A linear relationship diagram of solidification layer thickness and compressive strength of a long-life dust screen and dust suppression method thereof according to the present application;

[0049] Figure 5 A microscopic diagram of silt samples of a long-life dust screen and dust suppression method thereof according to the present application;

[0050] Figure 6 An XRD diagram of different reaction liquid volumes of a long-life dust screen and dust suppression method thereof according to the present application;

[0051] Figure 7 A linear relationship diagram of the influence of spraying mode on solidification effect of a long-life dust screen and dust suppression method thereof according to the present application;

[0052] Figure 8 A linear relationship diagram of the influence of reaction time on solidification effect of a long-life dust screen and dust suppression method thereof according to the present application. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0054] Please refer to the drawings in the embodiments of the present application Figure 1 - the drawings in the embodiments of the present application Figure 8 The present application provides a technical solution: a long-life dust screen and dust suppression method thereof, comprising: a dust screen main body and a surface treatment layer.

[0055] The surface treatment layer is a calcium carbonate deposition layer, and uniformly covers the surface of the dust screen to form a firm protective layer. This protective layer can effectively resist ultraviolet radiation, oxidation and chemical corrosion, and the dust screen main body is directly laid on the surface of the soil body and bonded together with the soil body through calcium carbonate deposition.

[0056] The base material of the dust screen main body can be polyester, polypropylene, nylon and other synthetic fibers. After EICP solution treatment, the durability of these materials is significantly improved

[0057] The formation of the calcium carbonate precipitation layer is that the EICP solution generates calcium carbonate precipitate through urease hydrolysis reaction and adheres to the surface of the dust screen and the contact point between the dust screen and the soil. Due to the presence of the calcium carbonate precipitation layer, the service life of the dust screen in harsh environments is prolonged, the replacement frequency due to material aging is reduced, and the treated dust screen can adapt to various climate conditions, including high temperature, low temperature, humidity change, etc., and maintain stable performance.

[0058] The preparation method of the EICP solution is as follows: S1, selecting raw materials, selecting soybeans as the source of urease; the calcium source can be calcium chloride (CaCl2), calcium acetate (C4H6CaO4) or other calcium-containing compounds; urea (CO(NH2)2) is selected as the carbon source;

[0059] S2, preparing a pulverizer to crush soybeans to extract urease, preparing a mixing container to contain raw materials and solution, and then using a stirrer to ensure uniform mixing of the solution;

[0060] S3, a. Extracting urease: put soybeans into a pulverizer to crush them into powder, then mix them with 10 times the amount of water by stirring, let it stand for a period of time, then filter out the soybean residue through gauze to obtain a urease solution;

[0061] b. Dissolving calcium salt: add an appropriate amount of water to the mixing container, slowly add calcium salt, and continuously stir using a stirrer until the calcium salt is completely dissolved in water;

[0062] c. Adding carbon source: add urea as carbon source to the calcium salt solution, continue to stir the solution to ensure that the urea is completely dissolved, and the concentration ratio of calcium salt to urea is 1:1;

[0063] d. Preparing EICP solution: add an equal volume of urease solution to the calcium salt and urea mixture, then mix thoroughly;

[0064] S4, safety measures, during the entire preparation process, the operator should wear protective glasses, gloves and lab coats, and should ensure that the operation is carried out in good ventilation conditions;

[0065] The spraying equipment is an adjustable spray bottle that can control the spraying intensity and range to ensure that the solution can be uniformly sprayed.

[0066] The main control factors of the construction technology are: spraying volume, spraying sequence and reaction time, etc.; the reasonable dust suppressant spraying volume in sandy soil is 3.66-4.00 L / m 2 Since the silt particle size is smaller than that of sandy soil, it is necessary to verify the applicable spraying volume under the conditions of silt in Zhengzhou. The designed spraying volume gradient test is respectively: 0 L / m 2 , 1 L / m 2 , 2 L / m 2 , 3 L / m 2, 4L / m 2 , 5L / m 2 After curing, the surface strength was measured by digital push-pull force meter, and the shell thickness was measured by digital vernier caliper. The test groups and results are shown in Table 4.4.

[0067] Table 4.4 Test groups and results of different spraying volumes

[0068]

[0069]

[0070] Spraying sequence: EICP reaction product contains calcium carbonate, which will gather between soil particles and reduce the porosity of the soil, thereby preventing the penetration and diffusion of the solution in the soil. Therefore, the mixing and spraying sequence of the components in the EICP dust suppressant solution will determine the reaction solidification effect. The dust suppressant solution can be divided into three cases according to the mixing order: ① first mix and spray urease solution and urea solution, then spray calcium chloride solution; ② or first mix and spray urea solution and calcium chloride solution, then spray urease solution; ③ directly mix and spray. Test uses spray bottle I and spray bottle II to load different solutions according to the three spraying sequences, with an interval of 1h. Through area ratio calculation, the total volume of EICP solution sprayed on this sample is 120mL. By comparing the surface strength and shell thickness of the samples under different conditions, a reasonable reaction liquid mixing order is obtained. The test groups and results are shown in Table 4.5.

[0071] Table 4.5 Test groups and results of different mixing orders

[0072]

[0073] Reaction time: with the increase of EICP reaction time, urea is continuously decomposed to produce and combine with Ca 2+ in the solution to generate more calcium carbonate. With the continuous increase of calcium carbonate content, the surface strength and solidification layer thickness of the sample will also increase. To explore the relationship between the solidification effect of dust suppressant after spraying and the action time, the influence of reaction time on the solidification effect of EICP dust suppressant is analyzed. According to the EICP dust suppressant concentration and ratio obtained in the previous text, a cementing solution with a mass concentration of 1.25mol / L is prepared, mixed with an equal volume of soybean urease solution to prepare EICP solution, and sprayed on the surface of silt sample according to the spraying volume determined in 4.3.1.2. The surface strength and shell thickness of each sample were detected at 1h, 3h, 6h, 9h, 12h, 15h, 18h, 21h, 24h, 48h, 72h after spraying. The test groups and results are shown in Table 4.6.

[0074] Table 4.6 Test groups and results of different reaction times

[0075]

[0076] To explore the effect of different volume of EICP solution on silt reinforcement, the surface compressive strength and thickness of the solidified layer of soil samples prepared by different spraying volumes were measured, and the test results are shown in Table 1. Figure 2 As can be seen from the figure, when the spraying volume is small, the reaction solution cannot fully penetrate the silt, and only a thin crust layer is formed on the surface, which has limited solidification effect on the soil, resulting in low surface compressive strength of the sample. When the spraying volume is 1L / m 2 , the surface compressive strength of the sample is only 205.65kPa, and the surface solidified layer thickness is 12.04mm. With the increase of spraying volume, the penetration of the solution into the soil sample is more sufficient, and the surface compressive strength of the sample gradually increases. When the spraying volume is 4L / m 2 , the surface compressive strength of the sample is 752.20kPa, and the surface solidified layer thickness is 14.97mm. When the spraying volume continues to increase, the surface compressive strength and the solidified layer thickness increase slightly. When the spraying volume is 5L / m 2 , the surface compressive strength of the sample is about 742.4kPa, and the surface solidified layer thickness is 15.01mm. The reason is that with the increase of the application volume of the reaction solution, calcium carbonate precipitates are generated between the particles of the surface silt, which hinders the further penetration of the reaction solution, so the solidification effect also reaches a critical value. Therefore, the spraying volume of 4L / m 2 is selected in the subsequent spraying test;

[0077] The relationship between the solidified layer thickness and the surface compressive strength was analyzed, and it was found that with the increase of the solidified layer thickness, the surface compressive strength also increases, and there is a linear relationship between the two. The linear relationship curve between the solidified layer thickness and the compressive strength is as follows:

[0078] y=78.3499x-66.1416(R 2 =0.938)(4.2)

[0079] In the formula: y——surface compressive strength, kPa;

[0080] x——solidified layer thickness, mm.

[0081] The coupling function variance is 0.938, and all the measured values are within the 95% confidence interval of the function, so it can be considered that the surface compressive strength and thickness of the silt solidified layer in the actual construction follow this function relationship;

[0082] The cementing liquid concentration is 1.25mol / L, and the spraying volume is 3-5L / m 2The SEM and XRD scanning of the silt sample after EICP treatment were carried out, and the silt sample without spraying treatment was set as the control group in the micro scanning. The micro images obtained are shown in Figure 5 and Figure 6 ;

[0083] Compared with the untreated bare soil of (a)-(c), the silt after reaction solution treatment has obvious cementation phenomenon. As shown in Figure 5 (d)-(f), when the cementation solution concentration is 1.25 mol / L and the spraying volume is 3 L / m 2 , the generated CaCO3 crystal is usually cubic calcite, the inclusion layer is thin, and there is no large area of calcium carbonate crystal superposition. As shown in Figure 5 (g)-(i), when the cementation solution concentration is 1.25 mol / L and the spraying volume is 4 L / m 2 , the soil particles are completely wrapped by CaCO3 crystals, and in addition to calcite, there are also vaterite. These crystals make fine particles adsorbed on the surface of soil particles through their cementation, forming a calcium carbonate crystal inclusion layer and forming a bedding structure. As shown in Figure 5 (k)-(m), when the cementation solution concentration is 1.25 mol / L and the spraying volume is 5 L / m 2 , the sample generates rich CaCO3 crystals overlapping and interweaving on the surface of silt particles. In summary, when the cementation solution concentration is constant, with the increase of the spraying volume, the newly formed CaCO3 crystals will produce crystal precipitation on the surface of silt particles, which will significantly reduce the pore between soil particles. However, it is worth noting that when the spraying volume reaches a certain degree, the increase of the silt solidification effect is not obvious with the increase of the EICP solution spraying volume;

[0084] According to the XRD phase composition of the Zhengzhou silt and the plain soil after EICP treatment in Figure 6 , the compressive strength of the soil sample in Figure 3 was compared, and the change of the solidification strength of the soil sample caused by the change of the spraying volume of the dust suppressant was analyzed;

[0085] Figure 6 The relative diffraction intensity in reflects the relative content of the phase composition of the silt sample after EICP treatment. With the increase of the spraying volume, the diffraction peak value of each crystal also changes, which represents the change of the relative content of the generated crystal composition. Among them, the diffraction peak intensity of the crystal surface (100), (012), (101), (021), (112), (202), (023) representing quartz (SiO2) is reduced, especially at the diffraction angle of 26.7°, the diffraction peak intensity of the crystal surface (101) is reduced from 3985 at the spraying volume of 0 L / m 2 to 3 L / m 2 , respectively., 4L / m 2 , 5L / m 2 , 1434, 339, 717. In addition, in the crystal faces (111), (012), (211) representing vaterite and the crystal faces (110), (200) representing calcite, the corresponding diffraction peak intensity increases with the increase of spraying volume. This shows that with the increase of EICP reaction solution spraying volume, the proportion of SiO2 in the silt main component in the total material proportion decreases, because the relative proportion of CaCO3 in the sample gradually increases. The growth rule of CaCO3 is consistent with the growth rule of unconfined compressive strength, which further reveals the mechanism of EICP technology for solidifying silt, that is, the more sufficient the soybean urease-induced calcium carbonate reaction is, the more calcium carbonate is generated, and the better the physical and mechanical properties of the soil body after reinforcement will be. In addition, through the analysis of the test results, no additional diffraction peaks appear in the XRD spectrum, proving that spraying EICP solution of different volumes does not affect the generated crystal and crystal type;

[0086] In order to explore the influence of different spraying sequences of EICP solution components on the solidification effect, the soil samples are sprayed step by step according to the working conditions in Table 4.5, and the interval between the two sprays is 60 min. After the first solution is fully penetrated, the second spraying is carried out. After 3d curing at 25℃, the surface compressive strength and solidified layer thickness are measured respectively, and the test results are shown in Figure 7 ;

[0087] In working condition W1, urea and urease solution are sprayed first, and then calcium chloride solution is sprayed. In working condition W3, urea, urease and calcium chloride solutions are sprayed at the same time. The solidification effect of these two cases is not ideal. The reason is that in working conditions W1 and W3, urease solution and urea solution are first mixed, and then sprayed on the surface of silt, that is, the urea hydrolysis reaction starts early, which makes carbonate ions generated in the solution too early. Therefore, when calcium ions appear in the environment, calcium carbonate precipitates will be quickly generated and cemented with soil particles, which hinders the penetration of surface solution into deep soil, resulting in that the compressive strength and solidified layer thickness of the treated soil cannot achieve the expected effect. In working condition W2, the urea hydrolysis and calcium carbonate precipitation reaction only starts after the urease solution is sprayed, so the EICP solution can fully penetrate and diffuse in the deep silt, ensuring that the solidified layer thickness and soil compressive strength achieve better effect. Based on this, the subsequent test will continue to use working condition W2 in order to get better solidification effect;

[0088] In order to explore the influence of different reaction times on the solidification effect, the sample is divided into multiple areas, and the surface strength of the corresponding area is measured at different reaction times. The test results are shown in Figure 8 ;

[0089] As shown in Figure 8As shown, the initial curing effect is improved rapidly. With the surface strength of the 72h cured sample as the reference value of the curing effect, the curing effect can reach 80% at 15h and 90% at 24h. With the further progress of the calcium carbonate precipitation reaction, a cemented and cured layer of calcium carbonate and silt is formed on the surface of the sample, preventing the reaction solution from further penetrating into the soil body. Thereafter, the unreacted solution in the deep layer of the soil body will continue to precipitate to form more calcium carbonate crystals until the reaction is completed. As can be seen from the results, the EICP curing reaction proceeds rapidly in the early stage, and the reaction rate gradually decreases over time. In practical engineering applications, the reaction time can be adjusted according to the required curing effect and time requirements to achieve optimal benefits.

[0090] The long-life dust screen dust suppression method comprises the following steps:

[0091] S1, using clean water and neutral cleaner to thoroughly clean the dust screen, remove the surface dust, oil stains and other impurities;

[0092] S2, after cleaning, check whether the dust screen is damaged or deformed, ensure that the net surface is complete and has no defects affecting the treatment effect;

[0093] S3, according to the material and environmental conditions of the dust screen, prepare EICP solution with appropriate concentration and viscosity.

[0094] S4, use professional spraying equipment such as high-pressure spray gun to evenly spray EICP solution on the dust screen, ensure that every part can fully contact the solution;

[0095] S5, the EICP solution reacts chemically and gradually forms calcium carbonate precipitate on the surface of the dust screen and between the dust screen and the soil particles.

[0096] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can make equivalent replacement or change according to the technical solution and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A dust suppression method for a long-life dust screen, characterized by, The long-life dust screen comprises a dust screen body and a surface treatment layer, the surface treatment layer is a calcium carbonate precipitation layer and uniformly covers the surface of the dust screen to form a solid protective layer, and the dust screen body is directly laid on the surface of the soil body and bonded with the soil body through the calcium carbonate precipitation layer; The base material of the dust screen body is a synthetic fiber of polyester, polypropylene or nylon; The calcium carbonate precipitation layer is formed by the urease hydrolysis reaction of the EICP solution to generate calcium carbonate precipitation and adhere to the surface of the dust screen and the contact point between the dust screen and the soil body; The preparation method of the EICP solution is as follows: S1, selecting raw materials, selecting soybeans as the source of urease, calcium chloride (CaCl2) or calcium acetate (C4H6CaO4) as the calcium source, and urea (CO(NH2)2) as the carbon source; S2, preparing a pulverizer to pulverize soybeans to extract urease, preparing a mixing container to contain raw materials and solution, and then using a stirrer to ensure uniform mixing of the solution; S3, a. Extracting urease: Put soybeans into the pulverizer to pulverize them into powder, then mix them with 10 times the amount of water by stirring, let stand for a period of time, then filter out the soybean residue through gauze to obtain a urease solution; b. Dissolving calcium salt: Add an appropriate amount of water to the mixing container, slowly add calcium salt, and continuously stir using a stirrer until the calcium salt is completely dissolved in water; c. Adding carbon source: Add urea as a carbon source to the calcium salt solution, continue to stir the solution to ensure that the urea is completely dissolved, and the concentration ratio of calcium salt to urea is 1:1; d. Preparing EICP solution: Add an equal volume of urease solution to the calcium salt and urea mixture, then mix thoroughly; S4, safety measures, during the entire preparation process, the operator should wear protective glasses, gloves and lab coats, and should ensure that the operation is carried out in good ventilation conditions; The long-life dust screen dust suppression method comprises the following steps: S1, thoroughly clean the dust screen with clean water and a neutral cleaner to remove dust, oil stains and other impurities on the surface; S2, after cleaning, check whether the dust screen is damaged or deformed to ensure that the screen surface is complete and has no defects that affect the treatment effect; S3, according to the material and environmental conditions of the dust screen, prepare an appropriate concentration and viscosity of EICP solution; S4, use a professional spraying equipment, the professional spraying equipment is a high-pressure spray gun, uniformly spray the EICP solution on the dust screen to ensure that every part can fully contact the solution; S5, the EICP solution undergoes a chemical reaction to gradually form calcium carbonate precipitation on the surface of the dust screen and between the dust screen and the soil particles.

2. The dust suppression method of the long-life dust screen according to claim 1, characterized in that, The spraying equipment is an adjustable sprinkler that can control the spraying intensity and range to ensure that the solution can be uniformly sprayed.

3. The dust suppression method of a long-life dust screen according to claim 2, characterized in that, The main control factors of the construction process are: spraying volume, spraying sequence and reaction time.

4. The dust suppression method of a long-life dust screen according to claim 3, characterized in that, The spraying volume: the reasonable dust suppressant spraying volume in sandy soil is 3.66~4.00L / m 2 Because the silt particle size is smaller than that of sandy soil, it is necessary to verify the applicable spraying volume under the condition of Zhengzhou silt. The spraying sequence: the EICP reaction product contains calcium carbonate, which will gather between soil particles and reduce the porosity of the soil, thereby preventing the penetration and diffusion of the solution in the soil; therefore, the mixing and spraying sequence of the components in the EICP dust suppressant solution will determine the reaction solidification effect; The reaction time: with the increase of EICP reaction time, urea is continuously decomposed to produce Ca2+ in the solution, combined with more calcium carbonate; 2+ combined with more calcium carbonate; With the increasing of calcium carbonate content, the surface strength and the thickness of the solidified layer of the sample will also increase; To explore the relationship between the solidification effect of dust suppressant after spraying and the action time, the influence of reaction time on the solidification effect of EICP dust suppressant was analyzed.

5. A method of dust suppression by a long-life dust screen according to claim 4, characterized in that, To explore the effect of different volumes of EICP solution on the reinforcement of silt, the surface compressive strength and thickness of the solidified layer of the soil sample prepared by different spraying volumes need to be measured.

6. The dust suppression method of a long-life dust screen according to claim 5, characterized in that, The relationship between the thickness of the solidified layer and the surface compressive strength was analyzed, and it was found that with the increase of the thickness of the solidified layer, the surface compressive strength also increased, and there was a linear relationship between them. The linear relationship curve between the thickness of the solidified layer and the compressive strength is as follows: where: y = surface compressive strength, kPa; x —— is the thickness of the solidified layer, mm; The coupling function variance is 0.938, and all the measured values are within the 95% confidence interval of the function, so the surface compressive strength and thickness of the silt solidified layer in actual construction follow this function relationship.

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