CN112457859A - Degradable multi-entanglement soil repair material - Google Patents

Abstract

The invention provides a degradable multi-entanglement soil remediation material which comprises the following components in parts by weight: 30-75% of natural fiber, 5-25% of synthetic fiber, 3-20% of polymer-based water absorbent, 3-10% of adhesive and 5-10% of natural porous material; the synthetic fiber is one or more of polyvinyl acetate, polylactic acid and polyacrylic acid; the water absorbent with the high molecular group is one or more of polyacrylamide copolymer, sodium polyacrylate and acrylonitrile grafted starch. The invention can bear the scouring of a great deal of water flow through the multi-stage structure consisting of natural fibers and synthetic fibers, and can protect soil to a certain extent so as to avoid water and soil loss; a large number of micropores are provided for the transportation of nutrition and oxygen of seeds and roots, so that the germination rate of the plant seeds is greatly improved. The material of the invention can be completely degraded in natural environment within one to two years, thereby avoiding secondary pollution. Meanwhile, the preparation process is simple and is suitable for large-scale production.

Description

Degradable multi-entanglement soil repair material

Technical Field

The invention relates to the technical field of ecological environment protection, in particular to a degradable multi-entanglement soil remediation material.

Background

In nearly two thirty years, with the acceleration of the basic construction and the development of urbanization of China, the vegetation in a plurality of cultivated lands, soil slopes and mountainous regions is damaged, which not only reduces the number of green plants, but also causes the bad ecological phenomena of water and soil loss, sand storm, rapid reduction of species number and the like. The land and the side slope are regreened, so that various ecological crises can be greatly reduced, and the method is the first step for gradually improving the ecological environment. The fiber covering is an ideal environment-friendly material for the slope, can prevent soil erosion due to the mechanical property and the water absorption capacity of the fiber covering. The water absorption allows seeds and seedlings to be in more complete contact with water for longer periods of time, thereby optimizing seed germination and vegetation growth. The cover is sufficiently open that air can easily penetrate the cover to promote plant growth. Synthetic fibers degrade more slowly than natural fibers and therefore control soil erosion over a longer period, typically up to 1 year.

A wide variety of fibre mulch is used in slope greening engineering to increase the germination rate of grass seeds and reduce soil erosion to enable seedlings to grow securely in the planting area. These coverings generally consist of natural materials, such as straw, wood chips or paper. The mulch is mixed with water and placed in a tank to be stirred and then sprayed onto the bed, some of which are woven into a blanket to be placed under the bed. Such coverings are functional, do absorb and store some water, so that the bed contains more water than when they are not in use, and they also block a portion of the rain, reducing soil erosion to a certain extent, and increasing the chances of green growth on slopes. However, most of these coverings are fibers that are not bonded to each other, are loosely structured, and are easily washed away. Paper-based coverings typically bond to a mat like concrete paper, thereby impeding the transmission of oxygen and sunlight and preventing the seedlings from penetrating the covering to continue growing, which can affect the growth of vegetation.

There is also a class of sprayable chemically bonded natural fiber coverings on the market. These coverings use a vegetable adhesive to bind the natural fibers together. Although such coverings are so tightly bound that the covering and the plant seed are difficult to wash away by running water. However, the chemically bonded covering forms a nearly impermeable layer on the bed, limiting the transport of water and oxygen required for plant growth. Furthermore, the cover layer itself makes it difficult for the germinating seeds to penetrate through. Coverings lacking fibers that mechanically bond to each other are difficult to absorb the energy of raindrops splashing, are themselves easily corroded, and cannot withstand prolonged, concentrated water flow scours. Thereby causing soil erosion.

Artificial fibers composed of polyester, polypropylene, and other man-made polymers are combined with each other to form a matrix through which germinated seeds, air, water, and light can pass to the soil surface. However, these synthetic fibers are not easily biodegradable and easily cause secondary pollution to the environment.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, and provides a degradable multi-entanglement soil remediation material, which has numerous micro-entanglement structures inside and can be used on a steep slope. And the vegetation yield of the newly sown seedbed can be improved, the water absorption of the seedbed is increased, and the water loss in the covered area is reduced.

In order to solve the technical problems, the invention adopts the technical scheme that: a degradable multi-entanglement soil remediation material comprises the following components in parts by weight: 30-75% of natural fiber, 5-25% of synthetic fiber, 3-20% of polymer-based water absorbent, 3-10% of adhesive and 5-10% of natural porous material;

the synthetic fiber is one or more of polyvinyl acetate, polylactic acid and polyacrylic acid; the water absorbent with the high molecular group is one or more of polyacrylamide copolymer, sodium polyacrylate and acrylonitrile grafted starch.

Further, the length of the natural fiber is 0.5 cm-3 cm, and the natural fiber is one or more of deciduous wood fiber, cotton fiber, wool fiber, flax fiber, jute fiber, coconut shell fiber, cellulose fiber, cotton fiber, cellulose xanthate (rayon), cellulose acetate, cellulose triacetate and cellulose nitrate.

Further, the binder is one or more of agar, carrageenan, gel, pectin and pectin or chitosan.

Further, the natural porous material is one or more of perlite, vermiculite, zeolite, fuller's earth, diatomite, clay, bentonite, montmorillonite, beidellite and nontronite.

Further, the surface of the synthetic fiber is sprayed with a layer of nontoxic degradable coating, and the nontoxic degradable coating comprises one or more of methylol urea resin, phenol formaldehyde resin, melamine formaldehyde resin, urea formaldehyde resin and furfural resin derivatives.

In order to solve the technical problem, the invention adopts another technical scheme that: a preparation method of a degradable multi-entanglement soil remediation material comprises the following steps:

s1, soaking the synthetic fiber in the coating solution, stirring for 10min, and drying at 30-50 ℃;

s2, adding synthetic fibers and natural fibers into a high-speed stirrer in an air atmosphere, and stirring at 1000rpm for 10-30 min until the synthetic fibers and the natural fibers are fully and uniformly mixed to obtain a fiber blend A;

s3, adding the fiber blend A into a long guide tube with a hot air fan, further uniformly mixing the blended fibers at high temperature for 5-20 min by using hot air at 50-70 ℃, and providing heat to curl the synthetic fibers containing the coating to prepare a mechanically-bonded fiber blend B;

s4, adding the fiber blend B, the polymer-based water absorbent, the adhesive and the natural porous material into a mechanical blending box, and stirring at 1500rpm for 10-30 min to prepare the degradable multi-entanglement soil remediation material.

Compared with the prior art, the invention has the beneficial effects that: the multi-stage structure formed by natural fibers and synthetic fibers can bear the scouring of great water flow, can form certain protection to soil and avoid water and soil loss; a large number of micropores are provided for the transportation of nutrition and oxygen of seeds and roots, so that the germination rate of the plant seeds is greatly improved. The material of the invention can be completely degraded in natural environment within one to two years, thereby avoiding secondary pollution. Meanwhile, the preparation process is simple and is suitable for large-scale production.

Detailed Description

It is easily understood that according to the technical solution of the present invention, a person skilled in the art can propose various alternative structures and implementation ways without changing the spirit of the present invention. Therefore, the following detailed description is merely illustrative of the technical solutions of the present invention, and should not be construed as being all of the present invention or limiting or restricting the technical solutions of the present invention.

A degradable multi-entanglement soil remediation material comprises the following components in parts by weight: 30-75% of natural fiber, 5-25% of synthetic fiber, 3-20% of polymer-based water absorbent, 3-10% of adhesive and 5-10% of natural porous material;

mainly composed of natural fibers and a small amount of crimped synthetic fibers, which are mixed well to form a mechanically bonded fibrous covering in which the synthetic fibers function as a bonding entity. The water absorbent of the polymeric matrix may also provide some binding.

The natural fiber is pine and larch fiber, cotton fiber, wool fiber, flax fiber, jute fiber, coconut fiber, hemp fiber, straw, grass or other fiber directly available from nature, and chemically modified natural fiber, such as chemically modified cellulose fiber, cotton fiber, etc., preferably cellulose acetate, man-made protein fiber (regenerated natural protein), regenerated cellulose product including at least one of cellulose xanthate (rayon), cellulose acetate, cellulose triacetate, cellulose nitrate, alginate fiber, casein-based fiber. The length of the natural fiber is 0.5 cm-3 cm.

The synthetic crimped fiber is at least one of polyvinyl acetate, polylactic acid and polyacrylate. Preferably, the mass fraction of the synthetic crimped fibers is about 10%. The ideal fibers are relatively short (one-half length natural fibers) crimped polyvinyl acetate fibers that bond to each other and to the mulch fibers to form an open, mechanically bonded fiber matrix that remains intact on steep slopes but is open enough to allow water and oxygen to pass to the seedbed and allow seedlings to grow through it.

Synthetic fibers may not be easily mechanically crimped. Such as in a partially intermeshing toothed roll, and the resulting product does not continue to retain its curl in subsequent applications, particularly in high humidity (e.g., rainy weather) environments. It is also possible that these products lose their curling properties after they are added to the composite can. Thus, the crimping process must be carried out under conditions that can cause thermal (e.g., plasticization) or chemical changes (e.g., cross-linking or degradation to an adhesive-like product), such fibers still remaining crimped under light and moisture. Therefore, the synthetic crimped fibers should be coated with a coating to maintain their crimped nature without modifying the fibers themselves. Such a coating material includes at least one of methylol urea resin, phenol-formaldehyde resin, melamine-formaldehyde resin, urea-formaldehyde resin, and furfural resin derivative. These coatings can impart crimp to synthetic fibers during proper heating, and are non-toxic and degradable, and are useful in part as fertilizers.

Preferably, one fiber should contain four to eight crimp points. Too much crimped fiber can result in too much entanglement, which can make it difficult to mix uniformly in a sprayer and difficult to use. Synthetic fibers having too few crimp points cannot be sufficiently bonded to the fibers of the cover, and the effect of the present invention cannot be achieved. In the case of using crimped fibers having a small degree of crimp, for example, one to three crimp points, the amount of crimped fibers used may be larger. Since the crimped fibers used are biodegradable, they can be used in large amounts without being limited by environmental requirements.

The water absorbent with high molecular group is at least one of polyacrylamide copolymer, sodium polyacrylate and acrylonitrile grafted starch, and powder is generally used preferably.

Preferably, the polymer-based water absorbent is a powdery polyacrylamide copolymer, and the water absorption capacity in water is tens of times of its own mass.

The binder is at least one of agar, carrageenan, gel, pectin, colla Corii Asini, chitosan, polyacrylamide, sodium polyacrylate, and starch.

The natural porous material is at least one of perlite, vermiculite, zeolite, fuller's earth, diatomite, clay, bentonite, montmorillonite, beidellite and nontronite. Preferably, the clay-based ceramic porous ceramic particles are more effective. These porous ceramic particles are inorganic soil additives to store water and oxygen streams to the roots of plants in easily packed tight soils. The porous ceramic particles are small enough in size to facilitate bonding and use in a viscous hydraulic blanket matrix. In the development of sprayable mulch products, the smaller the porous particle size, the better the moisture retention and dispersion in the mulch matrix.

A degradable multi-entanglement soil remediation material is prepared by the following steps:

s1, soaking the synthetic fiber in the coating solution, stirring for 10min, and drying at 30-50 ℃.

And S2, adding the synthetic fibers and the natural fibers into a high-speed stirrer in an air atmosphere, and stirring at 1000rpm for 10-30 min until the synthetic fibers and the natural fibers are fully and uniformly mixed to obtain the fiber blend A.

S3, adding the fiber blend A into a long guide pipe with a hot air fan, further uniformly mixing the blended fibers at high temperature for 5 to 20min by using hot air at the temperature of 50 to 70 ℃, and providing heat to enable the synthetic fibers containing the coating to be curled to prepare a mechanically bonded fiber blend B.

S4, adding the fiber blend B, the high molecular water absorbent, the adhesive and the natural porous material into a mechanical blending box, and stirring at 1500rpm for 10min to 30min to prepare the degradable multi-entanglement soil remediation material.

In order to achieve better plant planting effect, some biological growth regulators, such as indoleacetic acid, indolebutyric acid, soil improvement agents, pesticides, fertilizers and the like, can also be added into the fiber blend B in S3.

The invention is further illustrated by the following examples:

example 1

The degradable multi-entanglement soil remediation material is characterized by comprising the following components in parts by weight: 30% of wood fiber, 25% of flax fiber, 25% of cotton fiber, 5% of vinyl acetate fiber, 5% of sodium polyacrylate water absorbent, 3% of agar binder and 7% of clay porous material.

The length of the wood fiber, the flax fiber and the cotton fiber is 1cm to 1.5 cm.

The length of the vinyl acetate fiber is 0.4mm to 0.7 mm.

The particle diameter of the clay porous material is 20-30 μm.

The degradable multi-entanglement soil remediation material of the example is prepared by the following method:

(1) soaking vinyl acetate fiber in the furfural resin solution, stirring for 10min, and drying at 40 deg.C.

(2) Adding wood fiber, flax fiber, cotton fiber and vinyl acetate fiber into a high-speed stirrer in air atmosphere, and stirring at 1000rpm for 15min until fully and uniformly mixing to obtain a fiber blend A.

(3) Adding the fiber blend A into a long guide pipe with a hot air fan, further uniformly mixing the blended fibers at high temperature for 15min by using hot air at 70 ℃, providing heat, curling the synthetic fibers with the coating, and preparing the mechanically bonded fiber blend B.

(3) And then adding the fiber blend B, the sodium polyacrylate water absorbent, the agar adhesive and the clay porous material into a mechanical blending box, and stirring at 1500rpm for 30min to prepare the degradable multi-entanglement soil remediation material.

Example 2

The degradable multi-entanglement soil remediation material is characterized by comprising the following components in parts by weight: 55% of wood fiber, 20% of cotton fiber, 7% of polylactic acid fiber, 10% of sodium polyacrylate water absorbent, 3% of pectin binder and 5% of montmorillonite porous material.

The length of the wood fibers and the cotton fibers is 1cm to 1.5 cm.

The length of the polylactic acid fiber is 0.4mm to 0.6 mm.

The particle diameter of the montmorillonite porous material is 30-40 μm.

The degradable multi-entanglement soil remediation material of the example is prepared by the following method:

(1) soaking polylactic acid fiber in furfural resin solution, stirring for 10min, and oven drying at 40 deg.C.

(2) Adding wood fiber, cotton fiber and polylactic acid fiber into a high-speed stirrer in an air atmosphere, and stirring at 1000rpm for 15min until the mixture is fully and uniformly mixed to obtain a fiber blend A.

(3) Adding the fiber blend A into a long guide pipe with a hot air fan, further uniformly mixing the blended fibers at high temperature for 15min by using hot air at 60 ℃, providing heat to enable the synthetic fibers with the coating to be curled, and preparing the mechanically bonded fiber blend B.

(3) And then adding the fiber blend B, the sodium polyacrylate water absorbent, the pectin binder and the montmorillonite porous material into a mechanical blending box, and stirring at 1500rpm for 30min to prepare the degradable multi-entanglement soil remediation material.

Example 3

The degradable multi-entanglement soil remediation material is characterized by comprising the following components in parts by weight: 40% of wood fiber, 20% of cotton fiber, 10% of coconut shell fiber, 10% of polylactic acid fiber, 10% of polyacrylamide water absorbent, 5% of chitosan binder and 5% of diatomite porous material.

The length of the wood fiber, the coconut fiber and the cotton fiber is 1cm to 1.5 cm.

The length of the polylactic acid fiber is 0.4mm to 0.6 mm.

The diameter of the diatomite porous material is 30-40 μm.

The degradable multi-entanglement soil remediation material of the example is prepared by the following method:

(1) soaking polylactic acid fiber in hydroxymethyl urea resin solution, stirring for 10min, and oven drying at 35 deg.C.

(2) Adding wood fiber, coconut shell fiber, cotton fiber and polylactic acid fiber into a high-speed stirrer in an air atmosphere, and stirring at 1000rpm for 15min until the materials are fully and uniformly mixed to obtain a fiber blend A.

(3) Adding the fiber blend A into a long guide pipe with a hot air fan, further uniformly mixing the blended fibers at high temperature for 15min by using hot air at 50 ℃, providing heat to enable the synthetic fibers containing the coating to be curled, and preparing the mechanically bonded fiber blend B.

(3) And then adding the fiber blend B, the polyacrylamide water absorbent, the chitosan binder and the diatomite porous material into a mechanical blending box, and stirring at 1500rpm for 30min to prepare the degradable multi-entanglement soil remediation material.

Example 4

The degradable multi-entanglement soil remediation material is characterized by comprising the following components in parts by weight: 40% of wood fiber, 20% of cotton fiber, 10% of coconut shell fiber, 15% of polylactic acid fiber, 7% of polyacrylamide water absorbent, 4% of pectin binder and 4% of bentonite porous material.

The length of the wood fiber, the coconut fiber and the cotton fiber is 1cm to 1.5 cm.

The length of the polylactic acid fiber is 0.4mm to 0.6 mm.

The particle diameter of the diatomite porous material is 30-40 μm.

The degradable multi-entanglement soil remediation material of the example is prepared by the following method:

(1) soaking polylactic acid fiber in urea-formaldehyde resin solution, stirring for 10min, and drying at 35 deg.C.

(2) Adding wood fiber, coconut shell fiber, cotton fiber and polylactic acid fiber into a high-speed stirrer in an air atmosphere, and stirring at 1000rpm for 15min until the materials are fully and uniformly mixed to obtain a fiber blend A.

(3) Adding the fiber blend A into a long guide pipe with a hot air fan, further uniformly mixing the blended fibers at high temperature for 15min by using hot air at 50 ℃, providing heat to enable the synthetic fibers containing the coating to be curled, and preparing the mechanically bonded fiber blend B.

(3) And then adding the fiber blend B, the polyacrylamide water absorbent, the pectin binder and the bentonite porous material into a mechanical blending box, and stirring at 1500rpm for 20min to prepare the degradable multi-entanglement soil remediation material.

The example material and the comparative example (containing only 90% of natural fiber and 10% of water-retaining agent) are sprayed on 5 scouring slopes of 1m by 1m, and the slopes of the 5 scouring slopes are 30 degrees, 40 degrees, 50 degrees and 60 degrees respectively. The rainwater strength of the scouring slope is respectively 25mm/h, 50mm/h and 100 mm/h. Each scouring slope was subjected to a 60 minute rain scouring experiment for each rain intensity. And collecting the content of the silt in the runoff after the scouring is finished, and weighing and recording after the runoff is dried.

The invention relates to a soil remediation material artificial rainfall erosion measuring result

The technical scope of the present invention is not limited to the above description, and those skilled in the art can make various changes and modifications to the above-described embodiments without departing from the technical spirit of the present invention, and such changes and modifications should fall within the protective scope of the present invention.

Claims (6)

1. A degradable multi-entanglement soil remediation material is characterized by comprising the following components in parts by weight: 30-75% of natural fiber, 5-25% of synthetic fiber, 3-20% of polymer-based water absorbent, 3-10% of adhesive and 5-10% of natural porous material;

the synthetic fiber is one or more of polyvinyl acetate, polylactic acid and polyacrylic acid; the water absorbent with the high molecular group is one or more of polyacrylamide copolymer, sodium polyacrylate and acrylonitrile grafted starch.

2. The degradable multi-entangled soil remediation material of claim 1, wherein said natural fibers are 0.5 to 3cm in length and are one or more of deciduous wood fibers, cotton fibers, wool fibers, flax fibers, jute fibers, coir fibers, cellulose fibers, cotton fibers, cellulose xanthate (rayon), cellulose acetate, cellulose triacetate, and cellulose nitrate.

3. The degradable multi-entanglement soil remediation material of claim 1, wherein the binder is one or more of agar, carrageenan, gelatin, pectin, or chitosan.

4. The degradable multi-entangled soil remediation material of claim 1 wherein said natural porous material is one or more of perlite, vermiculite, zeolite, fuller's earth, diatomaceous earth, clay, bentonite, montmorillonite, beidellite, nontronite.

5. The degradable multi-entangled soil remediation material of claim 1 wherein said synthetic fiber surface is sprayed with a non-toxic degradable coating comprising one or more of methylol urea resin, phenol formaldehyde resin, melamine formaldehyde resin, urea formaldehyde resin, furfural resin derivatives.

6. A preparation method of a degradable multi-entanglement soil remediation material is characterized by comprising the following steps:

s1, soaking the synthetic fiber in the coating solution, stirring for 10min, and drying at 30-50 ℃;

s2, adding synthetic fibers and natural fibers into a high-speed stirrer in an air atmosphere, and stirring at 1000rpm for 10-30 min until the synthetic fibers and the natural fibers are fully and uniformly mixed to obtain a fiber blend A;

s3, adding the fiber blend A into a long guide tube with a hot air fan, further uniformly mixing the blended fibers at high temperature for 5-20 min by using hot air at 50-70 ℃, and providing heat to curl the synthetic fibers containing the coating to prepare a mechanically-bonded fiber blend B;

s4, adding the fiber blend B, the polymer-based water absorbent, the adhesive and the natural porous material into a mechanical blending box, and stirring at 1500rpm for 10-30 min to prepare the degradable multi-entanglement soil remediation material.