CN111285643A

CN111285643A - Slope protection material and preparation method, application and production equipment thereof

Info

Publication number: CN111285643A
Application number: CN202010207916.XA
Authority: CN
Inventors: 孔明; 张毅敏; 高月香; 晁建颖; 许雪婷; 杨飞; 刘茹; 王磊; 仇洁
Original assignee: Nanjing Institute of Environmental Sciences MEE
Current assignee: Nanjing Institute of Environmental Sciences MEE
Priority date: 2020-03-23
Filing date: 2020-03-23
Publication date: 2020-06-16
Anticipated expiration: 2040-03-23
Also published as: CN111285643B

Abstract

The invention discloses a slope protection material and a preparation method, application and production equipment thereof, and belongs to the field of novel materials. The slope protection material is prepared from cement, fermented plant straws and foaming agents, the used raw materials are simple, and the slope protection material is pressed into slope protection bricks after specific pretreatment and is used for river slopes and/or riverways of plain river network areas, so that effective slope protection can be achieved, the ecological water conservancy environment of the plain river network areas can be improved, the self-purification capacity of water bodies can be effectively improved, and the effect of preventing the hydraulic erosion of levee slopes can be effectively achieved; meanwhile, the invention provides a slope protection material preparation device which is reasonable in structural arrangement.

Description

Slope protection material and preparation method, application and production equipment thereof

Technical Field

The invention belongs to the field of novel materials, and particularly relates to a novel and environment-friendly slope protection material, and a preparation method, application and production equipment thereof.

Background

In plain river network areas, due to the characteristics that the water change rate of a river channel is low, soil around the river is mainly soft soil, and the like, the environment capacity of the river channel is low, and the bank slope erosion phenomenon is large. Particularly, in the dry season, the main water quality index shows a tendency of significantly rising. In recent years, ecological revetments have attracted more and more attention as important research directions for environmental governance of drainage basins. The ecological slope protection can prevent water and soil loss, reduce the pore water pressure of the slope body, intercept rainfall, weaken splash corrosion and control soil particle loss; can improve the environmental function and recover the damaged ecological environment.

The problem to be solved by slope protection mainly comes from two aspects. Firstly, the earth surface soil is eroded by water power, so that water and soil resources and soil productivity are damaged and lost, in plain river network areas, the main effect is the dissolution effect of water flow, and the water flow is easy to dissolve the soil from gaps formed by slope protection splicing, so that the ecological slope protection effect on the market is poor; secondly, river water change rate in plain river network areas is low, and environmental capacity is low, so that the environmental self-cleaning capacity of the areas is poor.

Common engineering revetments mainly include vegetation protection and engineering protection. The common measures for protecting the slope surface include plastering, guniting, concrete spraying, masonry stone wall protection, slope protection, color net spraying slope protection, plant protection and the like by mortar or three-layer soil and the like. Slope protection materials also range from initially single grouted or dry block stone embankments to the use of more ecological new materials (e.g., ecological bricks, gabions, etc.) and concrete materials. The mortar-laid or dry-laid rock block revetment, cast-in-place concrete revetment and the like are designed and constructed only from the aspects of meeting the stability of the side slope of the river channel and the functions of flood control and drainage of the river channel, and the influence on the environment and the ecology is not considered; the application of gabion in large quantity leads to the shortage of stone materials at present. Therefore, the invention and application of the novel ecological slope protection material are the trend of river course slope protection development.

Based on this, chinese patent with patent number ZL 201610639399.7 discloses an ecological bank protection and a manufacturing method thereof, belongs to the technical field of environmental protection and ecological restoration, and solves the technical problems of serious water and soil loss at two banks of a river channel and severe river channel non-point source pollution. The ecological protection slope comprises a plurality of spherical monomers, the spherical monomers are stacked to form the ecological protection slope, each spherical monomer comprises a coating and a kernel, the coating is coated outside the kernel, and the coating is composed of diatomite powder and coal gangue powder. However, the main pollutant removal principle of the patent is adsorption, and the self-cleaning capacity for lifting rivers is limited. For another example, chinese patent application No. 201811285967.3 discloses an ecological slope protection concrete and a construction method thereof, including a base concrete layer with a thickness of 5cm, a water storage and moisture preservation concrete layer with a thickness of 5cm, and a surface layer concrete layer with a thickness of 3-5cm containing grass seeds; wherein the surface concrete comprises magnesium phosphate cement, sodium bicarbonate, raw planting soil and humus. The invention discloses a burst cementing material which is characterized in that magnesium phosphate cement is used as a cementing material, the compatibility of the cementing material with vegetation is solved by utilizing a neutral environment after the cementing material is coagulated and hardened, in addition, although releasable ammonia forms communicated pores in the concrete in the coagulating and hardening process of the magnesium phosphate cement and provides nutrients for the growth of the vegetation, and the sodium bicarbonate is added mainly for the purpose or has the function of being used as a pH buffering agent to adjust the pH value of the concrete to a range suitable for the growth of plants. However, in the use process of the concrete, due to the growth of the root system of the plant and the factors such as containing sand and planting soil, the water body of the river can still enter the bank slope soil in a permeating mode, so that the soil is dissolved, the phenomenon that nutrient substances such as carbon, nitrogen and phosphorus in humus contained in the water body flow out easily occurs, the abnormal water quality index of the water body exceeds the standard, and the environmental risk of secondary pollution exists.

Disclosure of Invention

1. Problems to be solved

The invention provides a novel and environment-friendly slope protection material and a preparation method thereof, wherein the used raw materials are simple, and the slope protection material is pressed into slope protection bricks after specific pretreatment and is used for river slopes and/or riverways in plain river network areas, so that effective slope protection can be achieved, the ecological water conservancy environment in plain river network areas is improved, the self-cleaning capacity of water is effectively improved, and the effect of hydraulic erosion of levee slopes is prevented; meanwhile, the invention provides a slope protection material preparation device which is reasonable in structural arrangement.

2. Technical scheme

In order to solve the problems, the technical scheme adopted by the invention is as follows:

the slope protection material comprises a framework structure and pores, wherein the framework structure is formed by lightweight porous structure cement with hydroxyl groups loaded on the surface and plant straws with carboxyl groups loaded on the surface, and the pores are distributed in the framework structure.

The slope protection material is prepared from cement, fermented plant straws and a foaming agent.

The slope protection material is prepared from the following raw materials in parts by weight:

30-60 parts of cement

9-18 parts of fermented plant straw

1.25-20 parts of foaming agent

15-50 parts of water.

Preferably, the cement may be portland cement, aluminate cement, sulphoaluminate cement, aluminoferrite cement, fluoroaluminate cement, and phosphate cement, and the specific embodiment is partially illustrated herein by 425 sulphoaluminate cement as an example.

Preferably, the plant straw can be selected from wheat straw, rice straw or corn stalk core, and the specific embodiment is partially illustrated by taking the corn stalk core after fermentation as an example, wherein the corn stalk core is a product obtained by peeling the corn straw;

preferably, the fermentation mode of the plant straw is as follows: uniformly mixing the pretreated plant straws with inoculated sludge (the inoculum size is 30% of the mass of the plant straws) by adopting a one-time feeding batch operation mode, and carrying out dry anaerobic fermentation at the sealed fermentation temperature of 20-50 ℃ for 1-5 days. The fermentation produces 375 mg/g-450 mg/g of acetic acid, and the carboxyl content is 78.95 percent.

Preferably, the foaming agent is hydrogen peroxide.

In the preferable scheme, the density of the finished product of the slope protection material is 600-800 kg/m³And the compressive strength of the slope protection material is 12-20 MPa.

The preparation method of the slope protection material comprises the following steps:

1) preparation of lightweight cement with porous structure

Adding a foaming agent and cement into water, mixing, stirring and foaming for 1-2 hours to obtain lightweight cement with a porous structure;

2) preparation of the mixture

Mixing and stirring the fermented plant straws and lightweight porous structure cement for 2-3 hours to obtain a mixture;

3) water curing of mixed materials

Carrying out water retention maintenance on the prepared mixture for 2-4 days;

4) preparation of slope protection material

And carrying out extrusion forming and slicing treatment on the mixture.

Specifically, the preparation method of the slope protection material comprises the following steps:

1) preparation of lightweight cement with porous structure

Adding 1.25-20 parts of foaming agent hydrogen peroxide and 30-60 parts of cement into 15-50 parts of water, mixing, stirring and foaming for 1-2 hours to obtain lightweight porous structure cement;

2) preparation of the mixture

Mixing and stirring 9-18 parts of anaerobically fermented plant straws and lightweight porous structure cement for 2-3 hours to obtain a mixture;

3) water curing of mixed materials

Carrying out water retention maintenance on the prepared mixture for 2-4 days;

4) preparation of slope protection material

And carrying out extrusion forming and slicing treatment on the mixture.

The slope protection material is applied to the river slope and/or river channel of a plain river network area and is used for nursing the river slope and/or river channel.

Preferably, the slope protection material is paved on a river slope and/or a river channel of the plain river network area and is used for nursing the river slope and/or the river channel of the plain river network area.

The production equipment of the slope protection material comprises a sealed stirring tank, a stirring foaming tank and a mixing stirring tank which is respectively communicated with the sealed stirring tank and the stirring foaming tank through pipelines (regulating valves are arranged on the pipelines), wherein a material outlet of the mixing stirring tank is communicated with a cement block building machine (an XQ series customization machine of a Union mechanical factory in Ningxian county) through a pipeline (regulating valves are arranged on the pipelines);

the sealed stirring tank and the stirring foaming tank are positioned at the upper part; the mixing and stirring tank is positioned in the middle; the cement block machine is positioned at the lower part.

3. Advantageous effects

Compared with the prior art, the invention has the beneficial effects that:

(1) according to the novel slope protection material provided by the invention, the preparation raw materials (only cement, fermented plant straws and foaming agent are needed) are creatively selected, on one hand, the enrichment of microorganisms on the surface of the material is facilitated, a biological film is easy to form, and the film forming speed is high; on the other hand, the foaming agent is added to enable the material to form a porous structure inside, the fermented plant straw can provide a large amount of carboxyl to be enriched on the surface of the material, and the two coordinate effects greatly improve the adsorption capacity of the material on pollutants such as nitrogen and phosphorus.

(2) According to the novel slope protection material provided by the invention, hydrogen peroxide is selected as the foaming agent, so that a large amount of bubbles can be generated in the decomposition process, a porous structure is formed in the material, and meanwhile, a large amount of hydroxyl can be generated by water decomposition, and the hydroxyl and carboxyl provided by plant straws are enriched on the surface of the material together to form a large amount of hydrogen bonds with strong adsorption capacity, so that the adsorption capacity of the material on pollutants such as nitrogen, phosphorus and the like is further improved; meanwhile, nutrient elements are provided for the growth and development of microorganisms.

(3) The novel slope protection material provided by the invention is applied to nursing of river slopes and/or river channels, and has the following effects:

the water-proof slope protection material has strong slope protection capability, does not contain sandstone and soil raw materials, can quickly form a biological membrane on the surface of the slope protection material in a water body environment, can effectively prevent water flow from permeating/entering soil from gaps formed by splicing the material (the occurrence of gap water seepage is avoided without adopting a traditional cement cast-in-place construction process), leads to soil dissolution, can effectively maintain water and soil, ensures the water conservancy function of slope protection, and prevents the erosion of the water flow to a river slope and/or a river channel;

secondly, the water body environment capacity can be improved, and hydroxyl generated by hydrogen peroxide decomposition and carboxyl provided by fermented plant straws are enriched on the surface of the material to form hydrogen bonds with strong adsorption capacity, so that carbon, nitrogen, phosphorus and other substances in the water body can be effectively adsorbed, pollutants in the water body can be reduced, the water body self-purification capacity can be enhanced, and the water body environment capacity can be improved; on the other hand, the fermented plant straws can provide a large amount of carbon sources, so that enrichment of microorganisms on the surface of the material is facilitated, the microorganisms can maintain self survival through nutrients such as nitrogen and phosphorus adsorbed by hydrogen bonds on the surface of the material (the growth of the microorganisms needs not only the carbon sources but also the substances such as nitrogen and phosphorus), decomposition and rapid reduction of pollutants such as nitrogen and phosphorus in the water body can be further realized, the self-purification capacity of the water body is further enhanced, and the environmental capacity of the water body is improved; in addition, additional substances such as humus and the like are not required to be added into the material, so that the problems of over standard of unconventional water quality indexes and secondary pollution of a water body caused by outflow of nutrient substances such as carbon, nitrogen, phosphorus and the like contained in the humus are solved;

and thirdly, the device is particularly suitable for nursing the river slope and/or the river channel in the plain river network area with low river water change rate and low environmental capacity, and the later maintenance is simple.

(4) The novel slope protection material method provided by the invention has the advantages of simple steps and convenience in operation, is suitable for industrial production, and in the preparation process, the fermentation of the plant straws needs to be carried out separately from the preparation of lightweight porous structure cement, so that the process of anaerobic fermentation of the plant straws can be effectively prevented from being damaged, the generation of carboxyl is influenced, and the biomembrane forming effect and water quality pollutant adsorption effect of the final finished product are ensured to the maximum extent.

(5) The invention provides slope protection material production equipment which mainly comprises a sealed stirring tank, a stirring foaming tank, a mixing tank and a cement block building machine, and is of an upper layer framework, a middle layer framework and a lower layer framework, wherein the sealed stirring tank and the stirring foaming tank are positioned at the upper part, the mixing tank is positioned at the middle part, and a forming mold is positioned at the lower part, so that gravity transmission is realized, and energy conservation and high efficiency are realized; each reaction unit is controlled to enter and exit by a valve, so that the quality of a standardized finished product is ensured.

Drawings

Fig. 1 is a schematic structural view of a production facility for slope protection material provided by the present invention;

FIG. 2 is a schematic view of the slope protection material of the present invention laid when used for slope protection of river banks;

FIG. 3 is a water permeability coefficient testing apparatus;

in the figure: 1. sealing the stirring tank; 1.1, a first discharge port; 1.2, a first observation port; 1.3, a first pipeline; 1.4, a first stirring paddle; 1.5, a first tank body; 1.6, adjusting a valve I;

2. stirring the foaming tank; 2.1, a discharge hole II; 2.2, a second observation port; 2.3, ventilating openings; 2.4, a second stirring paddle; 2.5, a second tank body; 2.6, adjusting a valve II; 2.7, a second pipeline;

3. a mixing and stirring tank; 3.1, a third tank body; 3.2, a third stirring paddle; 3.3, a pipeline III; 3.4, adjusting a valve III;

4. a cement block machine; 4.1, discharging a mould; 4.2, cutting into pieces;

5. a fixed mount;

6. slope protection materials;

7. a stainless steel plate;

8. a concrete structure cushion layer;

9. river bank slope.

Detailed Description

The invention is further described with reference to specific examples.

It will be understood that when an element is referred to as being "mounted on" another element, it can be directly on the other element or the two elements can be directly connected together; when an element is referred to as being "connected" to another element, it can be directly connected to the other element or the two elements may be directly integrated. In addition, the terms such as "upper", "lower", "left", "right" and "middle" used in the present specification are for clarity of description only, and are not intended to limit the scope of the present invention, and changes or modifications of the relative relationship thereof may be made without substantial changes in the technical content.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

As used herein, a plurality of items, structural elements, compositional elements, and/or materials may be presented in a common list for convenience. However, these lists should be construed as though each member of the list is individually identified as a separate and unique member. Thus, no single member of such list should be construed as a de facto equivalent of any other member of the same list solely based on their presence in a common group without indications to the contrary.

Temperature and like numerical data may be presented herein in a range format. It is to be understood that such a range format is used merely for convenience and brevity and should be interpreted flexibly to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. For example, a numerical range of about 1 to about 4.5 should be interpreted to include not only the explicitly recited limit values of 1 to about 4.5, but also include individual numbers (such as 2,3, 4) and sub-ranges (such as 1 to 3, 2 to 4, etc.). The same principle applies to ranges reciting only one numerical value, such as "less than about 4.5," which should be construed to include all of the aforementioned values and ranges. Moreover, such an interpretation should apply regardless of the breadth of the range or feature being described.

Any steps recited in any method or process claims may be executed in any order and are not limited to the order presented in the claims. The limitations of method + function or step + function are only employed if all of the following conditions exist within the limitations of a particular claim: a) a method for or a step for is. b) The corresponding functions are explicitly described. Structures, materials, or acts that support the method + functions are explicitly recited in the description herein. The scope of the invention should, therefore, be determined only by the appended claims and their legal equivalents, rather than by the descriptions and examples given herein.

The production equipment of the novel slope protection material comprises a fixing frame 5 positioned for fixing a tank body, wherein the upper part of the fixing frame 5 is provided with a sealed stirring tank 1 and a stirring foaming tank 2, the middle part of the fixing frame is fixed with a mixing stirring tank 3, and the lower part of the fixing frame is fixed with a cement block building machine 4; the top of the sealed stirring tank 1 is provided with a discharge hole I1.1, one side of the tank body I1.5 is provided with an observation hole I1.2, the inside of the tank body I is provided with a stirring paddle I1.4, the bottom of the tank body I is communicated with the mixing stirring tank 3 through a pipeline I1.3, and the pipeline I1.3 is provided with an adjusting valve I1.6; the top of the stirring foaming tank 2 is provided with a discharge hole II 2.1, one side of the tank body II 2.5 is provided with a ventilation port 2.3 and an observation port II 2.2, the inside of the tank body II is provided with a stirring paddle II 2.4, the bottom of the tank body II is communicated with the mixing and stirring tank 3 through a pipeline II 2.7, and the pipeline II 2.7 is provided with an adjusting valve II 2.6. A third stirring paddle 3.2 is arranged in a third tank body 3.1 of the mixing and stirring tank 3, a discharge port is arranged at the lower part of the mixing and stirring tank, the discharge port is communicated with a cement block building machine 4 through a third pipeline 3.3, and a third regulating valve 3.4 is arranged on the third pipeline 3.3; a discharging die 4.1 and a material cutting sheet 4.2 are arranged in the die.

The pretreatment steps of the plant straws are as follows: the method comprises the steps of physically crushing plant straws, pretreating the crushed plant straws with 5% w (NaOH) solution for 7 days, then pretreating with 20% w (degrading bacteria for agricultural transportation) activated bacteria solution for 15 days, and turning piles at regular time every 2 days in the pretreatment process, wherein the particle size of the crushed plant straws is 3-8 mm. The sludge is anaerobic digested sludge taken from a pig manure anaerobic treatment plant, and is sieved to remove large impurities; the strain activation method of the activated bacterium liquid is as follows: diluting the powdery strain and distilled water according to the strain activation requirement of a manufacturer by the mass ratio of 1: 200, carrying out shaking culture at 37 ℃ for 24h at 150r/min, and counting the cultured strain to ensure the strain amount; the agricultural transportation degradation bacteria are purchased from Guangdong agricultural crown Biotech limited company, and the product number is as follows: CNC 1689368437. (the fermentation of plant straws, the pretreatment of the plant straws and the activation of strains of activated bacteria liquid are shown in the following articles: Chen bin, Yangtian, Gunn Yongyon, Wei Min, BeiDou, Zhao, Li Xue. corn straw dry anaerobic fermentation acetic acid production law and the influence on the fermentation [ J ] environmental science research, 2015,28(04):647 652.).

The mass of each portion described in the specific examples is 12 tons, but the claims are not limited thereto.

Example 1

The embodiment provides a slope protection material which is prepared from the following raw materials in parts by weight:

30 parts of cement, 18 parts of fermented plant straw, 2 parts of foaming agent and 50 parts of water; in the embodiment, a one-time feeding batch operation mode is adopted, pretreated plant straws (the grain diameter is 3-8 mm) and inoculated sludge (the inoculation amount is 30% of the mass of the plant straws) are uniformly mixed and sealed in a sealed stirring tank 1, dry anaerobic fermentation is carried out, the fermentation temperature is controlled to be 20-50 ℃, the fermentation time is 1 day, and the preparation method is obtained. The fermentation produced 375mg/g of acetic acid with a carboxyl content of 78.95%.

The slope protection material prepared by the equipment in the embodiment 1 specifically comprises the following steps:

1) preparation of lightweight cement with porous structure

Adding a foaming agent and cement into water for mixing, and stirring and foaming in a stirring foaming tank 2 for 2 hours to obtain lightweight cement with a porous structure;

2) preparation of the mixture

Mixing and stirring the fermented plant straws in the sealed stirring tank 1 and the lightweight porous structure cement in the stirring foaming tank 2 in a mixing and stirring tank 3 for 3 hours to obtain a mixture;

3) water-retention curing of mixed material

Conveying the prepared mixture into a discharging die 4.1 of a cement block machine 4, covering a preservative film on the surface of the mixture, and maintaining for 4 days in a water-retaining manner;

4) preparation of slope protection material

The mixture was extruded and cut into pieces by a cement block machine 4, and the slope protection material prepared in this example had a compressive strength of 12 MPa.

Example 2

40 parts of cement, 10 parts of fermented plant straws, 10 parts of foaming agent and 40 parts of water;

in the embodiment, a one-time feeding batch operation mode is adopted, pretreated plant straws (the particle size is 3-8 mm) and inoculated sludge (the inoculum size is 30% of the mass of the plant straws) are uniformly mixed and sealed in a sealed stirring tank 1, dry anaerobic fermentation is carried out, the fermentation temperature is controlled to be 20-50 ℃, the fermentation time is 3 days, and the preparation method is obtained. The fermentation produced 425mg/g, carboxyl content 78.95%.

1) preparation of lightweight cement with porous structure

Adding a foaming agent and cement into water, mixing, and stirring and foaming in a stirring foaming tank 2 for 1.5 hours to obtain lightweight porous structural cement;

2) preparation of the mixture

Mixing and stirring the fermented plant straws in the sealed stirring tank 1 and the lightweight porous structure cement in the stirring foaming tank 2 in a mixing and stirring tank 3 for 2.5 hours to obtain a mixture;

3) water curing of mixed materials

Conveying the prepared mixture into a discharging die 4.1 of a cement block machine 4, covering a preservative film on the surface of the mixture, and maintaining for 2 days in a water-retaining manner;

4) preparation of slope protection material

The mixture was extruded and cut into pieces by a cement block machine 4, and the slope protection material prepared in this example had a compressive strength of 20 MPa.

Example 3

At present, in plain river network areas, slope surface nursing is carried out on a certain river section by using the slope protection material produced by the method, and the slope protection material is laid on a river bank slope according to the mode shown in figure 2. The method comprises the following specific steps:

1. leveling the slope 9 of the river bank;

2. pouring a concrete structure cushion layer 8 on the bottom surface of the river channel;

3. the concrete structure bed course 8 of river course bottom surface begins, closely lays to bank slope 9 upper portion gradually, utilizes stainless steel 7 to fix the position of each piece bank protection material 6.

The indexes of main pollutants in the river water body are COD, ammonia nitrogen, total nitrogen and total phosphorus, after the slope protection material provided by the invention is laid, a biological film is quickly formed on the surface of the slope protection material, after the film is formed for one week, the content of the pollutants in the river at the section is reduced to different degrees, and the reduction range of the COD, the ammonia nitrogen, the total nitrogen and the total phosphorus reaches 50%, 30%, 40% and 38% respectively.

The slope protection material of the invention is prepared from 425 parts of sulphoaluminate cement 39 parts, 20 parts of fermented cornstalk core and 2 parts of hydrogen peroxide and 39 parts of tap water, and is produced in 6 batches (the mass of one part is 12 tons in the embodiment).

The production process of each batch is as follows:

1) preparation of fermented cornstalk core and lightweight porous structure cement

Preparing a fermented cornstalk core: adopt once to throw material batch operation mode, with the cornstalk core (the particle diameter is 3 ~ 8mm) after the preliminary treatment with inoculate mud (the inoculum size is 30% of plant straw quality) misce bene seal in sealed agitator tank 1, carry out dry-type anaerobic fermentation, the environment is seal structure, inside is equipped with the stirring rake. The fermentation temperature in the whole sealed stirring tank body is 20-50 ℃, the fermentation time is set to 5 days, the microorganisms in the anaerobic environment convert easily decomposed organic matters into acetic acid, the acetic acid with the concentration of 450mg/g is generated by fermentation, and the carboxyl content is 78.95%;

preparing lightweight porous structure cement: adding the ordinary 425 sulphoaluminate cement, hydrogen peroxide and water head into a stirring foaming tank 2 according to the proportion, and stirring for 1 hour for foaming;

2) preparation of the mixture

Mixing and stirring the fermented plant straws in the sealed stirring tank 1 and the lightweight porous structure cement in the stirring foaming tank 2 in a mixing and stirring tank 3 for 2 hours to obtain a mixture;

3) water curing of mixed materials

4) preparation of slope protection material

The mixture is extruded and molded by a cement block machine 4, and the material is cut into pieces by a cutting piece.

The final product has a density of 800kg/m³The compressive strength is 18 MPa.

Example 4

In a certain plain river network area, ecological building blocks are used as revetments in a river section with slow water flow, and the water and soil erosion phenomenon of different degrees occurs. The slope protection material produced by the method is used for slope surface nursing, and is laid on a river bank slope according to the mode shown in figure 2. The method comprises the following specific steps:

1. leveling the slope 9 of the river bank;

The indexes of main pollutants in the river water body are COD, ammonia nitrogen, total nitrogen and total phosphorus, after the slope protection material provided by the invention is laid, a biological film is quickly formed on the surface of the slope protection material, after the film is formed for one week, the content of the pollutants in the river at the section is reduced to different degrees, and the reduction range of the COD, the ammonia nitrogen, the total nitrogen and the total phosphorus reaches 60%, 35%, 60% and 40% respectively.

The slope protection material is prepared from 30 parts of 425 sulphoaluminate cement, 15 parts of fermented cornstalk core, 10 parts of hydrogen peroxide and 45 parts of tap water by weight, and is produced in 10 batches (each part is 12 tons in mass).

The production process of each batch is as follows:

1) the preparation of the fermented cornstalk core and lightweight porous structure cement,

2) preparation of the mixture

Mixing and stirring the fermented plant straws in the sealed stirring tank 1 and the lightweight porous structure cement in the stirring foaming tank 2 in a mixing and stirring tank 3 for 2 hours to obtain a mixture; a third step;

3) water curing of mixed materials

Conveying the prepared mixture into a discharging die 4.1 of a cement block machine 4, covering a preservative film on the surface of the mixture, and maintaining for 3 days in a water-retaining manner;

4) preparation of slope protection material

The final product has a density of 600kg/m³The compressive strength is 14 MPa.

Example 5

1. leveling the slope 9 of the river bank;

The main pollutant indexes in the river water body are COD, ammonia nitrogen, total nitrogen and total phosphorus, after the slope protection material provided by the invention is laid, a biological film is quickly formed on the surface of the slope protection material, the water body pollutant content in the river section is reduced in different degrees after the slope protection material is laid for one week, and the reduction range of the COD, the ammonia nitrogen, the total nitrogen and the total phosphorus respectively reaches 45%, 35%, 45% and 40%.

The slope protection material is prepared from 40 parts of 425 sulphoaluminate cement, 8 parts of fermented cornstalk core, 2 parts of hydrogen peroxide and 50 parts of tap water by mass, and is produced by 10 batches (each batch is 12 tons in mass).

The production process of each batch is as follows:

2) preparation of the mixture

3) water curing of mixed materials

Conveying the prepared mixture into a discharging die 4.1 of a cement block machine 4, covering a preservative film on the surface of the mixture, and maintaining for 2.5 days in a water-retaining manner;

4) preparation of slope protection material

The final product has a density of 700kg/m³The compressive strength is 17 MPa.

Comparative example 1

The following three different materials were prepared in this example.

The preparation method of the material one is basically the same as that of the material 4, and the differences are that:

the feed is prepared from the following raw materials in parts by weight:

80 parts of raw planting soil, 39 parts of 425 sulphoaluminate cement, 20 parts of humus (a product obtained after the anaerobic fermentation of common straws) and 39 parts of tap water;

the preparation process comprises the following steps:

1) preparing lightweight porous structure cement as in example 4;

2) preparation of the mixture

Mixing humus and lightweight porous structure cement in a stirring and foaming tank 2 in a mixing and stirring tank 3, adding raw planting soil, and stirring for 2 hours to obtain a mixture;

3) the mixture was water cured as in example 4;

4) slope protection materials were prepared as in example 4;

the density of the finished product of the prepared material I is 1200kg/m³The compressive strength is 30 MPa.

The preparation method of the second material is basically the same as that of the second material in example 4, and the differences are only that:

the preparation method is different, and the preparation process comprises the following steps:

1) adding the fermented cornstalk core, hydrogen peroxide and 425 sulphoaluminate cement into a stirring foaming tank 2 at the same time, stirring for 1 hour for foaming, and then mixing and stirring for 2 hours to obtain a mixture;

2) the mixture was water cured as in example 4;

3) slope protection materials were prepared as in example 4;

the density of the finished product of the prepared material II is 700kg/m³The compressive strength is 17 MPa.

The preparation method of the material III is basically the same as that of the material 4, and the differences are that:

the feed is prepared from the following raw materials in parts by weight:

425 parts of sulphoaluminate cement 39 parts, 20 parts of cornstalk core (not subjected to anaerobic fermentation, but simply physically crushed), 2 parts of hydrogen peroxide and 39 parts of tap water;

the preparation process comprises the following steps:

1) preparation of lightweight porous structure cement

2) preparation of the mixture

Mixing and stirring the cornstalk cores and lightweight porous structure cement in the stirring foaming tank 2 in a mixing and stirring tank 3 for 2 hours to obtain a mixture;

2) the mixture was water cured as in example 4;

3) slope protection materials were prepared as in example 4;

the density of the finished product of the prepared material III is 800kg/m³Compressive strength of 18MPa

Example 6

Under laboratory conditions, the materials in example 4 and comparative example 1 were subjected to biofilm formation and water purification capacity test;

respectively selecting four 1000mL beakers, adding 500mL of the water into the containers, standing/soaking for two weeks under natural conditions, and regularly detecting the biological films (the volatile dry weight (VSS) of the biological films, the TOC, the extracellular polymeric substances (polysaccharide and protein) of the biological films and the dehydrogenase activity of the biological films) on the surfaces of the materials every two days, the content of pollutants in the water after one week of an experimental period and the water permeability coefficient of each slope protection material (with the biological films) after two weeks of a film forming time.

The water quality is from natural surface water, and the content of COD, ammonia nitrogen, total nitrogen and total phosphorus in the water is 40mg/L, 2mg/L, 4mg/L and 0.4mg/L through inspection;

the method comprises the following steps of preparing a biological membrane, wherein the volatile dry weight (VSS) of the biological membrane, the TOC, the extracellular polymeric substances (polysaccharide and protein) of the biological membrane, the activity of dehydrogenase of the biological membrane and the water permeability coefficient are as follows:

1. detection of the biofilm:

first, exfoliation of biofilm

The biofilm is fixed on the surface of the carrier, and the dry weight of the biofilm is difficult to directly measure. Therefore, before evaluating the amount of carrier biofilm, the biofilm must first be peeled off from the carrier surface. The method comprises the steps of firstly placing a biological carrier in 1M alkali liquor, carrying out water bath for 30 minutes, controlling the temperature to be 60-80 ℃ so as to reduce the degree of crosslinking between the biological membrane and the surface of the carrier, and then carrying out ultrasonic treatment to obtain the peeled biological membrane.

Second, an index of the amount of biofilm is evaluated

The main evaluation indexes comprise biological membrane volatile dry weight (VSS), biological membrane TOC, biological membrane extracellular polymeric substances and biological membrane activity, and the detection method comprises the following steps:

(1) determination of biofilm volatile dry weight (VSS): drying the peeled biological membrane, after measuring the dry weight of the biological membrane, putting the sample in a muffle furnace at 550 ℃ to be burned to constant weight, and obtaining the weight loss of the total dry weight as a volatile biological membrane part.

The dry weight of the biofilm is reflected in the total amount of biofilm. The biochemical activity of the biological membrane is only related to the active biomass, and the volatile dry weight of the biological membrane reflects the content of organic components in the biological membrane and can reflect the active biomass of the biological membrane.

(2) Determination of total organic carbon content (TOC) of biofilm: measuring by adopting a Rovibond ET99731 TOC measuring instrument; the structural skeleton of the cell is mainly composed of organic carbon, and the change of the quantity of the biological membrane can be indirectly known by measuring the total organic carbon content of the biological membrane, namely TOC. Particularly, for microorganisms such as nitrified biomembranes and the like which grow slowly, the quantity of the biomembranes is generally less, and the direct dry weight method is inconvenient to measure, and under the condition, the analysis of the TOC of the biomembranes is more accurate.

(3) Biofilm Extracellular Polymers (EPS) are highly hydrated polymeric macromolecules in biofilms surrounding bacteria, the composition and physicochemical properties of which determine the adhesion, conformation and biological properties of biofilms; EPS is composed of a variety of organic substances, mainly polysaccharides and proteins, and therefore, in biofilm research, the EPS in a biofilm is often represented by the amount of extracellular polymeric polysaccharides and proteins in the biofilm, wherein

A. Determination of extracellular polymeric polysaccharide: the phenol-sulfuric acid colorimetric method is adopted, and the specific method is as follows: suspending the stripped biological membrane in the solution, adjusting the pH value to be neutral, and completely mixing; putting 1mL of suspended sample into a clean test tube, adding 1mL of 50g/L phenol solution, shaking and mixing for 10-20 s, adding 5mL of 95% sulfuric acid solution, and reacting for 10min in the dark; after the reaction is finished, oscillating for 10 s; finally, placing the test tube in a water bath at 20-30 ℃ for 10 min; after the water bath, colorimetric analysis was carried out at 490 nm.

B. Determination of proteins: coomassie brilliant blue method; the method has the advantages of simplicity, convenience, time saving and high accuracy. The specific analysis method is as follows: the first step is to prepare a Bradford reagent, 100mg of Coomassie brilliant blue G-250 is dissolved in 50mL of ethanol, then 100mL of 85% phosphoric acid solution is added, the mixture is vibrated gently and is uniform, finally ultrapure water is added, the volume is kept to 1000mL, and then the mixture is filtered, and the obtained filtrate is the Bradford reagent. The pH of the biofilm sample peeled off by ultrasonic alkali liquor is adjusted to be neutral by adding phosphoric acid. After completely mixing the biofilm suspension, 1mL of the sample was placed in a clean tube, and then 5mLBradford reagent was added thereto, and after mixing with shaking for 10 seconds, it was allowed to react in the dark for 10min. After completion, colorimetric analysis was carried out at 595 nm.

(4) Determination of biofilm activity: by triphenyltetrazolium chloride (TTC) -dehydrogenase activity assay. The microbial activity was expressed by the amount of TTC-formazan (TF), a reduction product of triphenyltetrazolium chloride (2,3, 5-triphenyltetrazolium chloride, TTC; Shanghai reagentCo., Ltd, Shanghai, China). The method mainly comprises the following steps:

A. preparation of biofilm samples

10g of carrier biological membrane is taken, rinsed for 2 times by distilled water, placed in a conical flask, and vigorously shaken by glass beads to break the biological membrane, diluted by 20mL of physiological saline, and stirred by a glass rod to form suspension for later use.

B. Main instruments and reagents

Dissolving 0.1g of TTC analytically pure and l g g of glucose in 100mL of distilled water, and storing in a brown reagent bottle; toluene (analytically pure); trichloromethane (analytically pure); tris-hydroxymethyl aminomethane (Tris) -HCI buffer solution, pH 8.6; and (3) the other: sodium sulfide.

C. Preparation of Standard Curve

L, 2,3, 4, 5 and 6mL of L g & L concentration were sequentially poured into a separating funnel^-1Mixing TTC-glucose standard solution, 2ml Tris-HCI buffer solution and lmL 10% Na2S new solution, and shaking up; after the solution is fully developed, accurately adding 5mL of toluene solution, shaking and completely extracting TF. Placing for a moment; after the solution is layered, taking out organic matterAnd moving the solution layer into an lcm cuvette, stabilizing for 2min, measuring a corresponding absorbance (A) value at a wavelength of 485nm by using an 752 ultraviolet spectrophotometer, drawing a graph of dehydrogenase activity, and drawing a standard curve by using a reagent blank as a control.

D. Biofilm dehydrogenase activity assay

Adding 2mL of the biomembrane preparation solution into a stoppered test tube, sequentially adding 2mL of Tris-HCl buffer solution, 0.1mol/L glucose solution and 0.5% TTC, putting the mixture into a thermostat at 37 +/-1 ℃ for culturing for 6h, taking the mixture out, adding 2 drops of concentrated sulfuric acid to terminate the reaction, accurately adding 5mL of toluene, shaking the mixture, centrifuging the mixture for 5min at 4000rpm, and taking an organic solvent layer for color comparison. Under the above conditions, the amount of 1. mu. gTF produced in 1 hour was 1 enzyme activity unit.

2. Determination of stable period of biofilm formation: the volatile dry weight (VSS) of the biological membrane is more than 5 mg/g; the TOC of the biological membrane is more than 1800mg/m²(ii) a Biofilm extracellular polymeric substance, polysaccharide is more than 45mg/L and protein is more than 50 mg/L; the activity of the biomembrane dehydrogenase is more than 2 mg/L.

3. Determination of biofilm thickness: the specific method refers to the biomembrane amount, thickness and activity [ J ] Zhaoqingliang, Liu Shu, Wang Yi Yu, Haerbin college of architecture, 1999(06) 39-43 in the composite biomembrane reactor.

4. Determination of Water Permeability (i.e. Permeability coefficient)

Reference is made to "study on the vibrating time of water-permeable concrete test blocks [ J ]. log flame, Liwei, Hunan institute of engineering (Nature's edition), 2011,21(03):76-80.) this test uses a simple water-permeability measuring device, which is shown in the following figure. The upper end and the lower end of the test piece are both open transparent frames, and the shape of the section of the test piece is the same as that of the section of the test piece. The front side is provided with scales, the periphery of a test piece is sealed by wax before measurement, then a water permeability instrument box is placed on the test piece, a joint between the box and the test piece is sealed by wax, then water is added into the box for more than 200mm, the water leaks through the test piece, the time is t1 when the horizontal plane descends to the scale of 160mm, and the time when the whole water in the box leaks is t 2.

The water permeability coefficient is divided into a variable water level coefficient and a fixed water level water permeability coefficient, the experiment takes the fixed water level water permeability coefficient as the water permeability coefficient, T2 is 160/T2,

wherein: t2 is the average water permeability coefficient in the process that the water level changes from 160mm to zero, and the unit is mm/s;

t2 is the time in s when all of the water in the box has leaked.

TABLE 1 biofilm formation and Water purification Capacity testing of materials in example 4 and comparative example 1

As can be seen from Table 1, the slope protection material prepared by the invention has short period of forming a biological film on the surface of the material, and can obviously remove pollutants in water during slope protection; the effective biological membrane has small water permeability coefficient after being formed on the surface of the material, and can effectively prevent water from entering soil in a permeation mode; the first material is added with the planting soil and humus, but in the long-term use process of the material, organic matters and phosphorus elements contained in the material are leaked due to soaking, and the unconventional water quality index of a water body exceeds the standard, so that the environmental risk of secondary pollution exists.

Claims

1. The slope protection material is characterized by being prepared from the following raw materials in parts by weight:

30-60 parts of cement

9-18 parts of fermented plant straw

1.25-20 parts of foaming agent

15-50 parts of water.

2. The slope protection material of claim 1, wherein the fermentation mode is dry anaerobic fermentation, the fermentation is sealed fermentation, the fermentation temperature is 20-50 ℃, and the fermentation time is 1-5 days.

3. The slope protection material of claim 2, wherein the fermented plant stalks are fermented cornstalk cores.

4. The slope protection material of any one of claims 1 to 3, wherein the foaming agent is hydrogen peroxide.

5. The slope protection material of claim 4, wherein the finished product density of the slope protection material is 600-800 kg/m³(ii) a The compressive strength is 12-20 MPa.

6. The preparation method of the slope protection material is characterized by comprising the following steps:

1) preparation of lightweight cement with porous structure

2) preparation of the mixture

3) water curing of mixed materials

Carrying out water retention maintenance on the prepared mixture for 2-4 days;

4) preparation of slope protection material

And carrying out extrusion forming and slicing treatment on the mixture.

7. The use of the slope protection material according to any one of claims 1 to 6, wherein the slope protection material is laid on a river slope and/or a river course for the care of the river slope and/or the river course.

8. The use of the slope protection material according to claim 7, wherein the slope protection material is laid on a river slope and/or a river channel of a plain river network area for the care of the river slope and/or the river channel of the plain river network area.

9. Production equipment of slope protection materials is characterized by comprising a sealed stirring tank, a stirring foaming tank and a mixing stirring tank which is respectively communicated with the sealed stirring tank and the stirring foaming tank through pipelines, wherein a material outlet of the mixing stirring tank is communicated with a cement block building machine;