Ecological slope protection method based on EICP combined with mushroom residues

Abstract

The invention discloses an ecological slope protection method based on EICP combined with mushroom dregs, which organically combines the EICP technology with the mushroom dregs, enhances the EICP reaction efficiency by utilizing the activity of organic matters and microorganisms in the mushroom dregs, and realizes the resource utilization of waste mushroom dregs at the same time. The method comprises the specific steps that the mushroom residues and EICP reaction liquid are mixed to be uniform on the clay slope surface, urea is promoted to be hydrolyzed through urease, calcium carbonate sediment is generated, and therefore the erosion resistance and stability of the slope surface soil body are enhanced. In addition, organic matters in the mushroom residues can improve the soil structure, promote the growth of plant roots, and further improve the ecological restoration effect of the slope. Compared with the prior art, the method has the advantages of being low in cost, environmentally friendly, easy and convenient to construct and the like, and is suitable for various slope ecological protection projects.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental engineering and ecological restoration, and specifically to an ecological slope protection method based on EICP combined with mushroom residue. Background Art

[0002] With the rapid development of infrastructure construction in China, a large number of exposed slopes have been formed, which are extremely prone to geological disasters such as soil erosion, landslides, and collapses, seriously threatening the safety of engineering and the stability of the ecological environment. Traditional slope protection methods mainly adopt engineering measures such as masonry with mortar rubble and concrete shotcrete. Although they can effectively improve the slope stability, they have disadvantages such as high cost, complex construction, and damage to the ecological environment.

[0003] Mushroom residue is the waste after edible mushroom cultivation, containing a large amount of organic matter and nutrient elements. At present, the treatment methods of mushroom residue mainly focus on stacking and landfill, which not only occupy land resources but also cause environmental pollution. Realizing the resource utilization of mushroom residue has become an urgent problem to be solved.

[0004] The information disclosed in this background art section is only intended to enhance the overall understanding of the present invention and should not be regarded as an admission or any form of suggestion that this information constitutes prior art already known to those of ordinary skill in the art. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the above technical defects and provide an ecological slope protection method based on EICP combined with mushroom residue. By organically combining the EICP technology with mushroom residue, the mushroom residue has a porous structure, which can provide more attachment sites for the generated calcium carbonate, promote the uniform distribution of calcium carbonate, and avoid the precipitation of the generated calcium carbonate concentrating on the soil surface. To a certain extent, it can overcome the defects of small pores in cohesive soil, easy blockage, and airtightness. The organic matter in mushroom residue has a certain pH buffering capacity, which can provide a suitable alkaline environment for the EICP reaction, promote the decomposition of urea and the formation of calcium carbonate precipitation. At the same time, the organic components (such as polysaccharides, proteins, etc.) in mushroom residue can be used as templates for biomineralization to guide the directional growth of calcium carbonate crystals and form a more stable crystal structure, thereby enhancing the mechanical properties of the soil. In addition, the mushroom residue contains a large amount of nutrients required for plant growth, which is beneficial to the growth and development of plants, so that the developed plant roots and the EICP mineralized layer can jointly anchor the slope. The present invention can realize the resource utilization of waste mushroom residue, utilize the organic matter and microbial activity in mushroom residue, enhance the EICP reaction efficiency, and achieve the stability and ecological restoration of slopes.

[0006] To solve the above problems, the technical solution of the present invention is an ecological slope protection method based on EICP combined with mushroom residue, including the following steps: S1. Raw material preparation: Crush and screen the mushroom residue for pretreatment to obtain mushroom residue particles with uniform particle size; Prepare the EICP reaction solution, and the EICP reaction solution contains urease solution and cementing solution; S2. Preparation of mixed slurry: Mix the pretreated mushroom residue with the EICP reaction solution in a certain proportion to obtain a mixed slurry; S3. Slope treatment: Mix the mixed slurry evenly on the slope to be repaired and carry out compaction treatment; S4. Curing: Cure the treated slope, keep the slope moist, promote the EICP reaction, until a stable calcium carbonate cementing layer is formed on the slope.

[0007] Preferably, the mushroom residue is obtained by crushing and screening the waste mushroom sticks after cultivating edible fungi such as Pleurotus ostreatus, Lentinula edodes, Flammulina velutipes, and Pleurotus eryngii.

[0008] Preferably, the preparation method of the urease solution in the EICP reaction solution is as follows: Preferably, in S1, select commercially available soybeans with a size of 0.5 cm - 1 cm, dry them at 40 - 60 °C and then crush them, and screen the soybean powder with a 0.3 - 0.8 mm sieve.

[0009] Preferably, in S2, mix the screened soybean powder and deionized water. According to the mass ratio, soybean powder: deionized water = 1:1. After stirring with a magnetic stirrer for 1 - 1.5 h, let it stand in a low-temperature environment of 4 °C - 12 °C for 20 - 24 h to obtain the supernatant of the mixture.

[0010] Preferably, in S3, pour the obtained supernatant of the mixture into a centrifuge tube, carry out centrifugation at a rotation speed of 3000 r / min - 6000 r / min and a temperature of 4 °C - 12 °C for 15 - 25 min to obtain the urease solution, and store the extracted urease solution at 2 - 5 °C for standby.

[0011] Preferably, the preparation method of the cementing solution in the EICP reaction solution is: Mix the anhydrous calcium chloride solution and the urea solution to obtain the cementing solution; According to the mass ratio, anhydrous calcium chloride solution: urea solution = 2:1.

[0012] Preferably, in the EICP reaction solution, according to the mass ratio, urease solution: cementing solution = 1:1.

[0013] Preferably, the mixing ratio of the mushroom residue to the EICP reaction solution is 2:1 (mass ratio).

[0014] Preferably, the mixed slurry is mixed evenly in the clay at 5% - 10% of the weight of the slope soil.

[0015] Preferably, the curing time is 7 - 28 days. During the curing period, the slope surface should be kept moist, and water - retaining materials can be covered or water can be sprayed regularly.

[0016] The present invention also provides an EICP - combined mushroom residue ecological slope protection structure, which includes a slope surface base layer, an EICP - residue mixed layer, and a vegetation layer; the EICP - residue mixed layer is prepared by the above - mentioned method. The vegetation layer is on the EICP - residue mixed layer and is improved soil containing seeds for plant germination and growth.

[0017] Preferably, the slope surface base layer is the original slope surface to be repaired or a slope surface after leveling treatment.

[0018] Preferably, the thickness of the EICP - residue mixed layer is 10 - 20 cm.

[0019] Preferably, the thickness of the vegetation layer is 3 cm, and the plant seeds are one or more of ryegrass, tall fescue, and bermudagrass. 30 - 40 g of plant seeds are incorporated per 1 m².

[0020] Preferably, the improved soil is slope clay and mushroom residue, and their mass ratio is 2:1. At the same time, 6% (based on the total mass of the main materials) of sodium carboxymethylcellulose is used as a binder.

[0021] The advantages of the present invention compared with the existing technology are as follows: 1. The present invention can improve the slope stability. By organically combining the EICP technology with mushroom residue, using the organic matter and microbial activity in the mushroom residue to enhance the urease activity, improve the EICP reaction efficiency, increase the soil strength and erosion resistance ability, thereby enhancing the slope stability.

[0022] 2. The present invention can promote plant growth: The organic matter in the mushroom residue improves the soil structure, increases soil fertility, provides a good environment for plant growth, and further consolidates the slope stability.

[0023] 3. The present invention realizes the resource utilization of waste residues: Applying mushroom residue to ecological slope protection realizes the resource utilization of waste, reduces environmental pollution, and has good economic and environmental benefits.

[0024] 4. The present invention is applicable to various slope ecological protection projects, especially to slopes such as soil slopes and weathered rock slopes that are prone to geological disasters such as soil erosion, landslides, and collapses. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is the slope surface structure diagram of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0026] To make the content of the present invention more clearly understood, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention.

[0027] Example 1: S1. Raw material preparation: Crush and screen the Flammulina velutipes residue to obtain residue particles with a particle size of 2 - 5 mm; Prepare the EICP reaction solution: By mass ratio, urease solution: cementing solution = 1:1. The preparation method of the urease solution is as follows: Select commercially available soybeans with a size of 0.5 cm, dry them at 50 °C and then crush them, screen the soybean powder with a 0.6 mm sieve, mix the screened soybean powder and deionized water, and by mass ratio, soybean powder: deionized water = 1:1. After stirring with a magnetic stirrer for 1 h, let it stand in a low-temperature environment at 5 °C for 24 h to obtain the supernatant of the mixture. Pour the supernatant into a centrifuge tube and perform centrifugation at a rotation speed of 5000 r / min and a temperature of 5 °C for 20 min to obtain the urease solution. Store the extracted urease solution at 5 °C for standby. In addition, the preparation method of the cementing solution is as follows: Mix the anhydrous calcium chloride solution and the urea solution to obtain the cementing solution; By mass ratio, anhydrous calcium chloride solution: urea solution = 2:1; S2. Preparation of the mixed slurry: Mix the pretreated Flammulina velutipes residue and the EICP reaction solution at a mass ratio of 2:1 and stir evenly to obtain the mixed slurry.

[0028] S3. Slope treatment: Select a soil slope as the test object, clean the loose soil and debris on the slope. The bottom layer is a slope after leveling. In the EICP-residue mixed layer, mix the mixed slurry with 10% of the weight of the slope soil in the clay, and the mixing thickness is about 15 cm. Cover a layer of non-woven fabric on the slope and use a spraying device to spray water regularly to keep the slope moist. The curing time is 20 days. Then lay a 3-cm-thick vegetation layer on the EICP-residue mixed layer. The vegetation layer is improved soil containing ryegrass seeds. The improved soil is slope clay and mushroom residue, and their mass ratio is 2:1. At the same time, it is equipped with 6% (based on the total mass of the main materials) of sodium carboxymethyl cellulose, and 40 g of ryegrass seeds are incorporated per 1 m².

[0029] Comparative Example 1: Comparative Example 1 provides an ecological slope protection method based on the enzyme-induced calcium carbonate precipitation (EICP) technology combined with mushroom residue. Compared with the example, Flammulina velutipes residue is not added in Comparative Example 1, and the remaining steps are the same as those in the example and will not be repeated here.

[0030] Comparative Example 2: Comparative Example 2 provides an ecological slope protection method based on the enzyme-induced calcium carbonate precipitation (EICP) technology combined with mushroom residue. Compared with the example, the EICP-residue mixed layer is not laid in Comparative Example 2, and only the ryegrass seeds are sown on the slope in the same way as in the example.

[0031] After the ryegrass grows to maturity, the vegetation coverage rate, the calcium carbonate production amount of the examples and Comparative Examples 1 and 2, and the soil erosion amounts in the examples and Comparative Examples 1 and 2 under the rainfall intensity of 80 mm / d are detected, and the results are shown in the following table.

[0032]

[0033] As can be seen from the table, the biomass of Example 1 is the highest. This is because the Flammulina velutipes residue contains a large amount of organic matter and nutrients required for plant growth, which can promote the growth of plant roots and subsequent growth and development, and improve the soil structure. Compared with Comparative Example 1, the calcium carbonate content in Example is relatively high. This is because the Flammulina velutipes residue improves the activity of urease in the EICP reaction solution during the formation of calcium carbonate, thereby enhancing the EICP reaction efficiency. Comparing the soil erosion amounts, the effect of Example 1 is the best, followed by Comparative Example 1. Under the action of rainfall scouring, in Example 1, due to the better plant growth and the relatively high calcium carbonate content, there are developed plant roots and cements to jointly resist rainfall erosion during rainfall scouring, so the slope protection effect is better.

[0034] The results show that: the calcium carbonate content in the slope soil body of the example is the highest, and the soil body strength and erosion resistance ability are enhanced compared with those of Comparative Examples 1 and 2; ryegrass is planted on the slope, and the biomass is observed. The ryegrass in the example grows well, and the preliminary effect of slope ecological restoration appears.

[0035] The above examples are only the preferred examples of the present invention, and do not limit the protection scope of the present invention. Any equivalent transformation based on the technical solution of the present invention belongs to the protection scope of the present invention.

Claims

1. An ecological slope protection method based on EICP combined with mushroom residue, characterized in that, It includes the following steps: S1. Crush and screen the mushroom residue pre-treatment to obtain mushroom residue particles with uniform particle size; S2. Mix the pre-treated mushroom residue with the EICP reaction solution in a certain proportion to obtain a mixed slurry; the EICP reaction solution includes urease solution and cementing solution; S3. Mix the mixed slurry evenly on the slope to be repaired and carry out compaction treatment; S4. Cure the treated slope, keep the slope moist, and promote the EICP reaction until a stable calcium carbonate cementing layer is formed on the slope.

2. The ecological slope protection method based on EICP combined with mushroom residue according to claim 1, characterized in that: The mushroom residue is obtained by crushing and screening the waste mushroom sticks after cultivating edible mushrooms such as Pleurotus ostreatus, Lentinula edodes, Flammulina velutipes, and Pleurotus eryngii.

3. The ecological slope protection method based on EICP combined with mushroom residue according to claim 1, characterized in that: In the EICP reaction solution, by mass ratio, urease solution: cementing solution = 1:

1.

4. A method for ecological slope protection based on EICP combined with mushroom residue according to claim 1, characterized in that: The mixing ratio of the mushroom residue to the EICP reaction solution is 2:

1.

5. The ecological slope protection method based on EICP combined with mushroom residue according to claim 1, wherein: The mixed slurry is evenly mixed in the clay at 5%-10% of the weight of the slope soil.

6. The ecological slope protection method based on EICP combined with mushroom residue according to claim 1, characterized in that: The curing time is 7-28 days. Keep the slope moist during the curing period, and the water retention material can be covered or water can be sprayed regularly.

7. An ecological slope protection structure based on EICP combined with mushroom residue, characterized in that: It includes a slope base layer, an EICP-mushroom residue mixed layer, and a vegetation layer; the EICP-mushroom residue mixed layer is prepared by the method described in any one of claims 1-6, and the vegetation layer is improved soil containing seeds on the EICP-mushroom residue mixed layer.

8. The EICP combined with mushroom residue ecological slope protection structure according to claim 7, characterized in that: The slope base layer is the original slope to be repaired or the slope after leveling treatment.

9. The EICP combined with mushroom residue ecological slope protection structure according to claim 7, characterized in that: The thickness of the EICP-mushroom residue mixed layer is 10-20 cm.

10. The EICP combined with mushroom residue ecological slope protection structure according to claim 7, characterized in that: The thickness of the vegetation layer is 3 cm, and the plant seeds are one or more of Lolium perenne, Festuca arundinacea, and Cynodon dactylon.

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