CN114342597A - Treatment method for deeply ploughing and diluting heavy metal polluted farmland - Google Patents
Treatment method for deeply ploughing and diluting heavy metal polluted farmland Download PDFInfo
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Abstract
The invention provides a method for treating farmland polluted by heavy metal through deep ploughing and dilution, and relates to the technical field of soil improvement. Which comprises the following steps: draining water and drying the farmland in the sun, and drying the farmland in the sun into dry land; respectively turning out the surface soil, the middle soil and the bottom soil through deep ploughing and separately stacking; applying a soil conditioner and quicklime on the middle-layer soil, backfilling to obtain new bottom-layer soil, and uniformly rotary tillage; applying a soil conditioner and quicklime on the surface soil, backfilling the soil on the new bottom soil to serve as new middle soil, and then carrying out rotary tillage and uniform mixing; applying biomass charcoal and organic fertilizer on the bottom layer soil, backfilling the bottom layer soil on the new middle layer soil to serve as new surface layer soil, and then carrying out rotary tillage and uniform mixing; the surface soil depth isH1The depth of the middle layer soil is H2The depth of the bottom soil is H3，5≤H1＜10cm，10≤H2＜20cm，20≤H3Less than or equal to 40 cm. The treatment method carries out layered treatment on the soil and has stable restoration effect.
Description
Technical Field
The invention relates to the technical field of soil improvement, in particular to a method for treating farmland polluted by heavy metal through deep ploughing and dilution.
Background
The self-cleaning and detoxifying capacity of the soil is limited, the interference of external factors cannot be completely resisted, if the total amount of external pollutants in the soil exceeds the buffering limit of the soil, the self-cleaning capacity of the soil is lost, and the pollution result cannot be reversed. From the condition that the types of pollutants exceed standards, the standard exceeding condition of various heavy metal pollutants is in a severe state, and the heavy metal pollutants can not only cause soil degradation and pollute surrounding water bodies, but also migrate into human bodies through the absorption and accumulation of food, thereby bringing unpredictable damage to human health.
The existing methods for repairing and treating heavy metal contaminated soil comprise physical repair technology, chemical repair technology, phytoremediation technology, microbial repair technology and the like, the physical repair technology comprises various methods such as soil improvement method (soil-cutting method, deep ploughing method, soil replacement method and the like), electric repair method, heat treatment method, vitrification technology and the like, and the chemical repair technology mainly comprises soil leaching method (extraction method) and chemical passivator repair method. The existing treatment method for heavy metal pollutants has unstable repair effect, is easy to cause secondary pollution, is not suitable for repairing and treating large-area heavy metal polluted soil, and has great use limitation.
Disclosure of Invention
The invention aims to provide a method for treating farmland polluted by heavy metal through deep ploughing and diluting, which treats soil layer by layer through a deep ploughing and soil turning method and has stable treatment effect.
The technical problem to be solved by the invention is realized by adopting the following technical scheme.
The embodiment of the application provides a method for treating a deeply ploughed diluted heavy metal polluted farmland, which comprises the following steps:
draining water and drying the farmland in the sun, and drying the farmland in the sun into dry land;
respectively turning out the surface soil, the middle soil and the bottom soil by a deep soil turning and improving method and then separately stacking;
applying a soil conditioner and quicklime on the middle-layer soil, uniformly mixing, and backfilling to obtain new bottom-layer soil;
applying a soil conditioner and quicklime on the surface soil, uniformly mixing, and backfilling on new bottom soil to serve as new middle soil;
applying biomass charcoal and organic fertilizer on the bottom layer soil, backfilling the bottom layer soil on the new middle layer soil to serve as new surface layer soil, and then carrying out rotary tillage and uniform mixing;
the depth of surface soil is H1The depth of the middle layer soil is H2The depth of the bottom soil is H3Wherein, H is more than or equal to 51＜10cm，10≤H2＜20cm，20≤H3≤40cm。
Compared with the prior art, the embodiment of the invention has at least the following advantages or beneficial effects:
the method comprises the steps of firstly discharging accumulated water in a farmland, then airing the farmland into dry land, wherein the water content of soil is too high, the sludge is too much, the permeability is weak, and the farmland is not suitable for crops planted in the dry land, so that the accumulated water in the farmland needs to be firstly discharged, and the farmland needs to be aired for a period of time; the surface layer soil, the middle layer soil and the bottom layer soil are respectively turned out and then are separately stacked by a deep ploughing method so as to be convenient for respectively treating the surface layer soil, the middle layer soil and the bottom layer soil in a targeted manner, and the soil can be more stably repaired after being respectively treated due to different degrees of heavy metal pollution of the surface layer soil, the middle layer soil and the bottom layer soil; applying a soil conditioner and quicklime in the deeply ploughed farmland, backfilling the middle layer soil, filling the middle layer soil into the bottom layer, and carrying out rotary tillage on the middle layer soil so that the middle layer soil is fully mixed with the soil conditioner and the quicklime to adsorb heavy metal ions in the middle layer soil; at the moment, the soil conditioner and the quicklime are applied again to the backfilled middle layer soil, then the surface layer soil is backfilled, the surface layer soil is filled into the middle layer, and rotary tillage is carried out on the surface layer soil, so that the surface layer soil, the soil conditioner and the quicklime are fully mixed; and applying the biomass carbon and the organic fertilizer to increase the soil fertility and adsorb heavy metals and organic pollutants in the soil. The invention respectively turns out the surface soil, the middle soil and the bottom soil by a deep ploughing method and treats the soil, adopts a method combining a physical repair technology and a chemical repair technology, is not easy to cause secondary pollution, has stable repair effect and is suitable for repairing and treating the large-area heavy metal polluted soil.
The soil conditioner adopted by the invention comprises the components of fly ash, sulfur, apatite, natural medical stone, salt modified medical stone, medical stone coated urea and modified sodium bentonite, can convert heavy metals in soil from a usable state to an unusable state, and reduces the activity and the mobility of the heavy metals in the soil, thereby reducing the biological toxicity of the heavy metals in the soil and reducing the migration and accumulation of the heavy metals in crop products, and has better improvement effect on farmlands polluted by the heavy metals, so that the soil conditioner is suitable for the planting of crops.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.
It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to specific examples.
A treatment method for deeply ploughing and diluting a heavy metal polluted farmland comprises the following steps:
draining water and drying the farmland in the sun, and drying the farmland in the sun into dry land;
respectively turning out the surface soil, the middle soil and the bottom soil by a deep soil turning and improving method and then separately stacking;
applying a soil conditioner and quicklime on the middle-layer soil, uniformly mixing, and backfilling to obtain new bottom-layer soil;
applying a soil conditioner and quicklime on the surface soil, uniformly mixing, and backfilling on new bottom soil to serve as new middle soil;
applying biomass charcoal and organic fertilizer on the bottom layer soil, backfilling the bottom layer soil on the new middle layer soil to serve as new surface layer soil, and then carrying out rotary tillage and uniform mixing;
the depth of surface soil is H1The depth of the middle layer soil is H2The depth of the bottom soil is H3Wherein, H is more than or equal to 51＜10cm，10≤H2＜20cm，20≤H3≤40cm。
In the embodiment, firstly, the accumulated water in the farmland is discharged, then the farmland is aired into dry land, the water content of the soil is too high, the sludge is too much, the permeability is weak, and the soil is not suitable for crops planted in the dry land, so that the accumulated water in the farmland needs to be firstly discharged and aired for a period of time; the surface layer soil, the middle layer soil and the bottom layer soil are respectively turned out and then are separately stacked by a deep ploughing method so as to be convenient for respectively treating the surface layer soil, the middle layer soil and the bottom layer soil in a targeted manner, and the soil can be more stably repaired after being respectively treated due to different degrees of heavy metal pollution of the surface layer soil, the middle layer soil and the bottom layer soil; applying soil conditioner and quicklime in the deeply ploughed farmland, and backfilling the middle layer soil, wherein the middle layer soil is filled into the bottom layerThen, carrying out rotary tillage on the soil, and fully mixing the middle layer soil with the soil conditioner and the quicklime to adsorb heavy metal ions in the middle layer soil; at the moment, the soil conditioner and the quicklime are applied again to the backfilled middle layer soil, then the surface layer soil is backfilled, the surface layer soil is filled into the middle layer, and rotary tillage is carried out on the surface layer soil, so that the surface layer soil, the soil conditioner and the quicklime are fully mixed; the method comprises the steps of applying biomass charcoal and organic fertilizer on backfilled surface soil, backfilling the bottom soil, carrying out rotary tillage and mixing uniformly, turning the bottom soil to the surface, applying the biomass charcoal and the organic fertilizer to increase soil fertility, adsorbing heavy metals and organic pollutants in the soil, fixing carbon and nitrogen, applying the soil to reduce CO2、N2O、CH4And the emission of greenhouse gases. The invention respectively turns out the surface soil, the middle soil and the bottom soil by a deep ploughing method and treats the soil, adopts a method combining a physical repair technology and a chemical repair technology, is not easy to cause secondary pollution, has stable repair effect and is suitable for repairing and treating the large-area heavy metal polluted soil.
In some embodiments of the present invention, the soil conditioner comprises fly ash, sulfur, apatite, natural Maifanitum, salt-modified Maifanitum, Maifanitum-coated urea, and modified sodium bentonite. In the above embodiment, the components of the soil conditioner can transform the heavy metals in the soil from the available state to the unavailable state through a series of chemical reactions such as precipitation, adsorption, complexation, ion exchange, oxidation reduction and the like, so as to reduce the activity and the mobility of the heavy metals in the soil, reduce the biological toxicity of the heavy metals in the soil and reduce the migration and accumulation of the heavy metals in crop products, and have a good improvement effect on farmlands polluted by the heavy metals, so that the soil conditioner is suitable for crop planting.
In some embodiments of the present invention, the soil conditioner comprises, by weight, 10-20 parts of fly ash, 3-7 parts of sulfur, 10-20 parts of apatite, 8-18 parts of natural medical stone, 8-18 parts of salt-modified medical stone, 3-7 parts of medical stone coated urea and 10-18 parts of modified sodium bentonite. In the embodiment, the natural medical stone has an obvious layered structure, a clear structure between layers, a spongy structure and small holes, so that the natural medical stone has certain adsorption capacity and has strong adsorption effect on Cu and Cd in soil; the salt solution of the medical stone after the salt modification treatment is fully permeated into the medical stone structure and is decomposed by chemical reaction with organic or inorganic impurities in the pores of the medical stone, so that the pore passages of the medical stone are dredged, the specific surface area is increased, and the adsorption effect is stronger; the medical stone coated urea can reduce the loss and volatilization of urea and has the function of slow release; the modified sodium bentonite has stronger cation exchange capacity and adsorption capacity, and has better improvement effect on the soil polluted by heavy metals.
In some embodiments of the present invention, the soil conditioner comprises 15 parts of fly ash, 5 parts of sulfur, 15 parts of apatite, 13 parts of natural medical stone, 13 parts of salt modified medical stone, 5 parts of medical stone coated urea and 14 parts of modified sodium bentonite by weight. In the above examples, the amount of each component in the soil conditioner is further limited to better exert the repairing effect of the soil conditioner.
In some embodiments of the present invention, the soil conditioner described above is prepared by the following method: the coal ash, sulfur, apatite, natural medical stone, salt modified medical stone, medical stone coated urea and modified sodium bentonite are crushed to be 800 meshes at 600 meshes, then are calcined at 850 ℃ at 800 meshes, and are mixed evenly to prepare the soil conditioner. In the above examples, the preparation method is simple. The powdery soil conditioner is prepared by the preparation method.
In some embodiments of the present invention, the salt-modified medical stone is prepared by the following method: placing natural Maifanitum in Na2SO4Soaking in the solution; then to Na2SO4Carrying out suction filtration on the solution, and simultaneously washing the filter cake with distilled water until the pH of the filtrate is 6.7-7.3; drying the filter cake at the temperature of 110-130 ℃ for 0.8-1.2h, grinding the filter cake into powder and sieving the powder through a sieve of 100-120 meshes to obtain the salt modified medical stone. In the above examples, the natural Maifanitum is treated with Na2SO4Modified medical stone watchThe surface becomes rough and loose, the phenomenon of lamellar fracture and crack occurs, and Na2SO4The reaction with the substances in the pore canal makes the pore canal enlarged, the pore canal distribution more uniform, the small crystal grain quantity increased, the specific surface area increased, thereby enhancing the absorption performance.
In some embodiments of the present invention, the maifanite coated urea is prepared by the following steps: and coating urea, coating adhesive and salt modified medical stone powder layer by an open type rotary coating process to obtain the medical stone coated urea. In the embodiment, the salt modified medical stone is used as the coating material, compared with the natural medical stone, the medical stone coated urea prepared by using the salt modified medical stone as the coating material can provide fertilizer efficiency and repair heavy metal polluted soil.
In some embodiments of the invention, the modified sodium bentonite is subjected to organic modification by adopting a pig manure degradation liquid through a wet process. In the embodiment, the pig manure degradation liquid is used as the modifier, the cost is low, and the sodium bentonite modified by the pig manure degradation liquid has better passivation capability on Cu in soil.
In some embodiments of the present invention, the biomass charcoal is prepared by pyrolyzing straws including rape straws, miscanthus straws and rice straws at a high temperature. In the embodiment, the rape straws have good passivation effect on Pb, Zn and Cd in soil, and the bioavailability and the migration capacity of Cd and Zn are remarkably reduced by the Chinese silvergrass straws and the rice straws.
In some embodiments of the invention, the amount of soil conditioner and quicklime applied to the mid-soil is reduced by 40-60% compared to the amount applied to the topsoil. In the embodiment, the amounts of the soil conditioner and the quicklime applied to the soil at different depths are limited, so that the soil conditioner and the quicklime cannot be used for improving the soil instead of being applied too much.
The features and properties of the present invention are described in further detail below with reference to examples.
Example 1
A treatment method for deeply ploughing and diluting a heavy metal polluted farmland comprises the following steps:
draining water and drying the farmland in the sun, and drying the farmland in the sun into dry land;
respectively turning out surface soil, middle soil and bottom soil by a deep soil turning and improving method and then separately stacking, wherein the depth of the surface soil is 8cm, the depth of the middle soil is 15cm, and the depth of the bottom soil is 30 cm;
applying 25 kg/mu of soil conditioner and 50 kg/mu of quicklime on the middle-layer soil, uniformly mixing, and backfilling to obtain new bottom-layer soil;
applying 50 kg/mu of soil conditioner and 100 kg/mu of quicklime on the surface soil, uniformly mixing, and backfilling on new bottom soil to serve as new middle soil;
applying 8 kg/mu of biomass charcoal and 12 kg/mu of organic fertilizer on the bottom layer soil, backfilling the soil on the new middle layer soil to serve as new surface layer soil, and then carrying out rotary tillage and uniform mixing
The soil conditioner is prepared by the following method: the soil conditioner is prepared by crushing 15kg of fly ash, 5kg of sulfur, 15kg of apatite, 13kg of natural medical stone, 13kg of salt modified medical stone, 5kg of medical stone coated urea and 14kg of modified sodium bentonite into 700 meshes, calcining at 830 ℃ and mixing uniformly.
The salt modified medical stone in the embodiment is prepared by the following method: placing natural Maifanitum in Na2SO4Soaking in the solution; then to Na2SO4Carrying out suction filtration on the solution, and simultaneously washing the filter cake with distilled water until the pH of the filtrate is 7.0; drying the filter cake at 120 deg.C for 1.0h, grinding into powder, and sieving with 110 mesh sieve to obtain the salt modified Maifanitum.
The medical stone coated urea in the embodiment is prepared by the following method: and (3) wrapping urea, a coating adhesive and salt modified medical stone powder by an open type rotary coating process to obtain the medical stone coated urea.
The modified sodium bentonite in the embodiment is subjected to organic modification by adopting a pig manure degradation liquid through a wet process.
The biomass charcoal in the embodiment is prepared by performing high-temperature pyrolysis on rape straws, Chinese silvergrass straws and rice straws.
Example 2
A treatment method for deeply ploughing and diluting a heavy metal polluted farmland comprises the following steps:
draining water and drying the farmland in the sun, and drying the farmland in the sun into dry land;
respectively turning out surface soil, middle soil and bottom soil by a deep soil turning and improving method and then separately stacking, wherein the depth of the surface soil is 5cm, the depth of the middle soil is 10cm, and the depth of the bottom soil is 20 cm;
applying 24 kg/mu of soil conditioner and 48 kg/mu of quicklime on the middle-layer soil, uniformly mixing, and backfilling to obtain new bottom-layer soil;
applying 40 kg/mu of soil conditioner and 80 kg/mu of quicklime on the surface soil, uniformly mixing, and backfilling on new bottom soil to serve as new middle soil;
applying 5 kg/mu of biomass carbon and 10 kg/mu of organic fertilizer on the bottom layer soil, backfilling the soil on the new middle layer soil to serve as new surface layer soil, and then carrying out rotary tillage and uniform mixing;
the soil conditioner is prepared by the following method: the soil conditioner is prepared by crushing 10kg of fly ash, 3kg of sulfur, 10kg of apatite, 8kg of natural medical stone, 8kg of salt modified medical stone, 3kg of medical stone coated urea and 10kg of modified sodium bentonite into 600 meshes, calcining at a high temperature of 800 ℃, and mixing uniformly.
The preparation methods of the salt modified medical stone, the medical stone coated urea, the modified sodium bentonite and the biomass charcoal in the embodiment are the same as the embodiment 1.
Example 3
A treatment method for deeply ploughing and diluting a heavy metal polluted farmland comprises the following steps:
draining water and drying the farmland in the sun, and drying the farmland in the sun into dry land;
respectively turning out surface soil, middle soil and bottom soil by a deep soil turning and improving method and then separately stacking, wherein the depth of the surface soil is 9cm, the depth of the middle soil is 19cm, and the depth of the bottom soil is 40 cm;
applying 24 kg/mu of soil conditioner and 44 kg/mu of quicklime on the middle-layer soil, uniformly mixing, and backfilling to obtain new bottom-layer soil;
applying 60 kg/mu of soil conditioner and 110 kg/mu of quicklime on the surface soil, uniformly mixing, and backfilling on new bottom soil to serve as new middle soil;
applying biomass charcoal 10 kg/mu and organic fertilizer 15 kg/mu on the bottom layer soil, backfilling on the new middle layer soil to serve as new surface layer soil, and then rotary tillage and uniform mixing;
the soil conditioner is prepared by the following method: 20kg of fly ash, 7kg of sulfur, 20kg of apatite, 18kg of natural medical stone, 18kg of salt modified medical stone, 7kg of medical stone coated urea and 18kg of modified sodium bentonite are crushed into 800 meshes, calcined at the high temperature of 850 ℃ and mixed uniformly to prepare the soil conditioner.
The preparation methods of the salt modified medical stone, the medical stone coated urea, the modified sodium bentonite and the biomass charcoal in the embodiment are the same as the embodiment 1.
Example 4
A treatment method for deeply ploughing and diluting a heavy metal polluted farmland comprises the following steps:
draining water and drying the farmland in the sun, and drying the farmland in the sun into dry land;
respectively turning out surface soil, middle soil and bottom soil by a deep soil turning and improving method and then separately stacking, wherein the depth of the surface soil is 6cm, the depth of the middle soil is 16cm, and the depth of the bottom soil is 35 cm;
applying 20.7 kg/mu of soil conditioner and 46.8 kg/mu of quicklime on the middle-layer soil, uniformly mixing, and backfilling to obtain new bottom-layer soil;
applying 46 kg/mu of soil conditioner and 104 kg/mu of quicklime on the surface soil, uniformly mixing, and backfilling on new bottom soil to serve as new middle soil;
applying 5 kg/mu of biomass carbon and 15 kg/mu of organic fertilizer on the bottom layer soil, backfilling the soil on the new middle layer soil to serve as new surface layer soil, and then carrying out rotary tillage and uniform mixing;
the soil conditioner is prepared by the following method: the soil conditioner is prepared by crushing 12kg of fly ash, 3kg of sulfur, 14kg of apatite, 12kg of natural medical stone, 18kg of salt modified medical stone, 5kg of medical stone coated urea and 18kg of modified sodium bentonite into 650 meshes, calcining at high temperature of 825 ℃, and mixing uniformly.
The preparation methods of the salt modified medical stone, the medical stone coated urea, the modified sodium bentonite and the biomass charcoal in the embodiment are the same as the embodiment 1.
Example 5
A treatment method for deeply ploughing and diluting a heavy metal polluted farmland comprises the following steps:
draining water and drying the farmland in the sun, and drying the farmland in the sun into dry land;
respectively turning out surface soil, middle soil and bottom soil by a deep soil turning and improving method and then separately stacking, wherein the depth of the surface soil is 5cm, the depth of the middle soil is 18cm, and the depth of the bottom soil is 40 cm;
applying 27.5 kg/mu of soil conditioner and 49.5 kg/mu of quicklime on the middle layer soil, uniformly mixing, and backfilling to obtain new bottom layer soil;
applying 50 kg/mu of soil conditioner and 90 kg/mu of quicklime on the surface soil, uniformly mixing, and backfilling on new bottom soil to serve as new middle soil;
applying 8 kg/mu of biomass charcoal and 10 kg/mu of organic fertilizer on the bottom layer soil, backfilling the soil on the new middle layer soil to serve as new surface layer soil, and then carrying out rotary tillage and uniform mixing;
the soil conditioner is prepared by the following method: the soil conditioner is prepared by crushing 18kg of fly ash, 6kg of sulfur, 18kg of apatite, 18kg of natural medical stone, 8kg of salt modified medical stone, 3kg of medical stone coated urea and 12kg of modified sodium bentonite to 750 meshes, calcining at a high temperature of 810 ℃, and mixing uniformly.
The preparation methods of the salt modified medical stone, the medical stone coated urea, the modified sodium bentonite and the biomass charcoal in the embodiment are the same as the embodiment 1.
Comparative example 1
In contrast to example 1, no soil conditioner was applied.
Comparative example 2
In comparison to example 1, a conventional farming was performed with the application of a soil conditioner.
Test examples
The method is characterized in that farmlands polluted by heavy metals in Royota county of Huanggang city, Hubei province are treated, farmlands with light pollution and farmlands with medium pollution are respectively selected for treatment, the sampling depth is 0-20cm, the root growth depth of crops growing on the farmlands is not more than 20cm, soil with the depth of 0-20cm is sampled for determination, the soil is comparable, the farmland is respectively treated by the treatment methods of the embodiment and the comparative example, the content of the heavy metals in the treated soil is determined, and the determination results are shown in the following table 1.
TABLE 1
As can be seen from Table 1, the heavy metal content of the soil treated by the treatment method of the present invention is significantly reduced compared to the soil treated by the conventional cultivation without the soil conditioner of the present invention, and the heavy metal content of the soil treated by the treatment method of the present invention is reduced compared to the soil treated by the conventional cultivation and the soil conditioner of comparative example 1, which shows that the heavy metal content of the soil can be reduced by the deep ploughing, and the heavy metal level of the soil can be significantly diluted by the treatment method of the deep ploughing with the soil conditioner.
Vegetables are planted on the treated soil, the influence of different treatment methods on the accumulation of heavy metals in the vegetables is measured, and compared with the GB 18406.1-2001 standard, and the measurement result is shown in Table 2.
TABLE 2
As can be seen from Table 2, compared with the GB 18406.1-2001 standard, the heavy metal content of the vegetables planted in the soil treated by the treatment method of the embodiment of the invention is below the standard critical value, the heavy metal content of the vegetables grown in the slightly polluted soil of the comparative example 1 is below the standard, and the heavy metal content of the vegetables planted in the moderately polluted soil of the comparative example 1 and the comparative example 2 is above the standard critical value, which indicates that the influence on the vegetables cannot be eliminated by only deep ploughing on the severely polluted soil.
In conclusion, the invention provides a method for treating farmland polluted by heavy metal through deep ploughing and diluting, which comprises the steps of firstly discharging accumulated water in the farmland, then airing the farmland into dry land, wherein the water content of soil is too high, the sludge is too much, the permeability is weak, and the farmland is not suitable for crops planted in the dry land, so that the accumulated water in the farmland needs to be firstly discharged, and the farmland needs to be aired for a period of time; the surface layer soil, the middle layer soil and the bottom layer soil are respectively turned out and then are separately stacked by a deep ploughing method so as to be convenient for respectively treating the surface layer soil, the middle layer soil and the bottom layer soil in a targeted manner, and the soil can be more stably repaired after being respectively treated due to different degrees of heavy metal pollution of the surface layer soil, the middle layer soil and the bottom layer soil; applying a soil conditioner and quicklime in the deeply ploughed farmland, backfilling the middle layer soil, filling the middle layer soil into the bottom layer, and carrying out rotary tillage on the middle layer soil so that the middle layer soil is fully mixed with the soil conditioner and the quicklime to adsorb heavy metal ions in the middle layer soil; at the moment, the soil conditioner and the quicklime are applied again to the backfilled middle layer soil, then the surface layer soil is backfilled, the surface layer soil is filled into the middle layer, and rotary tillage is carried out on the surface layer soil, so that the surface layer soil, the soil conditioner and the quicklime are fully mixed; and applying the biomass carbon and the organic fertilizer to increase the soil fertility and adsorb heavy metals and organic pollutants in the soil. The invention respectively turns out the surface soil, the middle soil and the bottom soil by a deep ploughing method and treats the soil, adopts a method combining a physical repair technology and a chemical repair technology, is not easy to cause secondary pollution, has stable repair effect and is suitable for repairing and treating the large-area heavy metal polluted soil.
The soil conditioner adopted by the invention comprises the components of fly ash, sulfur, apatite, natural medical stone, salt modified medical stone, medical stone coated urea and modified sodium bentonite, can convert heavy metals in soil from a usable state to an unusable state, and reduces the activity and the mobility of the heavy metals in the soil, thereby reducing the biological toxicity of the heavy metals in the soil and reducing the migration and accumulation of the heavy metals in crop products, and has better improvement effect on farmlands polluted by the heavy metals, so that the soil conditioner is suitable for the planting of crops.
The embodiments described above are some, but not all embodiments of the invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Claims (10)
1. A treatment method for deeply ploughing and diluting a heavy metal polluted farmland is characterized by comprising the following steps:
draining water and drying the farmland in the sun, and drying the farmland in the sun into dry land;
respectively turning out the surface soil, the middle soil and the bottom soil by a deep soil turning and improving method and then separately stacking;
applying a soil conditioner and quicklime on the middle-layer soil, uniformly mixing, and backfilling to obtain new bottom-layer soil;
applying a soil conditioner and quicklime on the surface soil, uniformly mixing, and backfilling on new bottom soil to serve as new middle soil;
applying biomass charcoal and organic fertilizer on the bottom layer soil, backfilling the bottom layer soil on the new middle layer soil to serve as new surface layer soil, and then carrying out rotary tillage and uniform mixing;
the depth of surface soil is H1The depth of the middle layer soil is H2The depth of the bottom soil is H3Wherein, H is more than or equal to 51＜10cm，10≤H2＜20cm，20≤H3≤40cm。
2. The method as claimed in claim 1, wherein the soil conditioner comprises fly ash, sulfur, apatite, natural Maifanitum, salt-modified Maifanitum, Maifanitum-coated urea and modified sodium bentonite.
3. The method for treating deeply ploughed diluted heavy metal contaminated farmland according to claim 2, wherein the soil conditioner comprises, by weight, 10-20 parts of fly ash, 3-7 parts of sulfur, 10-20 parts of apatite, 8-18 parts of natural medical stone, 8-18 parts of salt-modified medical stone, 3-7 parts of medical stone coated urea and 10-18 parts of modified sodium bentonite.
4. The method for treating deeply ploughed diluted heavy metal contaminated farmland according to claim 3, wherein the amount of each component in the soil conditioner is 15 parts by weight of fly ash, 5 parts by weight of sulfur, 15 parts by weight of apatite, 13 parts by weight of natural medical stone, 13 parts by weight of salt-modified medical stone, 5 parts by weight of medical stone coated urea and 14 parts by weight of modified sodium bentonite.
5. The method for treating deeply ploughed diluted heavy metal contaminated farmland according to any one of the claims 1 to 4, characterized in that the soil conditioner is prepared by the following method: the coal ash, sulfur, apatite, natural medical stone, salt modified medical stone, medical stone coated urea and modified sodium bentonite are crushed to be 800 meshes at 600 meshes, then are calcined at 850 ℃ at 800 meshes, and are mixed evenly to prepare the soil conditioner.
6. The method for treating farmland polluted by heavy metals through deep ploughing and diluting as claimed in claim 5, wherein the salt modified medical stone is prepared by the following method: placing natural Maifanitum in Na2SO4Soaking in the solution; then to Na2SO4Solution feedingCarrying out suction filtration, and simultaneously washing the filter cake with distilled water until the pH of the filtrate is 6.7-7.3; drying the filter cake at the temperature of 110-130 ℃ for 0.8-1.2h, grinding the filter cake into powder and sieving the powder through a sieve of 100-120 meshes to obtain the salt modified medical stone.
7. The method for treating deeply ploughing and diluting the heavy metal polluted farmland according to claim 5, wherein the medical stone coated urea is prepared by the following method: and (3) wrapping urea, a coating adhesive and salt modified medical stone powder by an open type rotary coating process to obtain the medical stone coated urea.
8. The method for treating deeply ploughing and diluting the farmland polluted by the heavy metals according to claim 5, characterized in that the modified sodium bentonite is subjected to organic modification by adopting a pig manure degradation liquid through a wet process.
9. The method for treating farmland polluted by heavy metals through deep ploughing and diluting as claimed in claim 1, wherein the biomass charcoal is prepared by high-temperature pyrolysis of straws including rape straws, miscanthus straws and rice straws.
10. The method as claimed in claim 1, wherein the amount of soil conditioner and quicklime applied to the middle soil is reduced by 40-60% compared with the amount applied to the surface soil.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109894469A (en) * | 2019-04-10 | 2019-06-18 | 河南工学院 | Medicament and restorative procedure are repaired for the efficient stableization of heavy-metal contaminated soil |
| CN110121969A (en) * | 2018-02-08 | 2019-08-16 | 中环循(北京)环境技术中心 | A kind of deep ploughing in repairing heavy metal pollution farmland is digged method |
| AU2020103884A4 (en) * | 2020-12-04 | 2021-02-11 | Institute Of Agricultural Resources And Environment, Shandong Academy Of Agricultural Sciences | A soil conditioner prepared from waste materials by biological fermentation bed and its preparation method |
| CN112808759A (en) * | 2020-12-31 | 2021-05-18 | 河南省地质环境规划设计院有限公司 | Heavy metal polluted farmland restoration method |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110121969A (en) * | 2018-02-08 | 2019-08-16 | 中环循(北京)环境技术中心 | A kind of deep ploughing in repairing heavy metal pollution farmland is digged method |
| CN109894469A (en) * | 2019-04-10 | 2019-06-18 | 河南工学院 | Medicament and restorative procedure are repaired for the efficient stableization of heavy-metal contaminated soil |
| AU2020103884A4 (en) * | 2020-12-04 | 2021-02-11 | Institute Of Agricultural Resources And Environment, Shandong Academy Of Agricultural Sciences | A soil conditioner prepared from waste materials by biological fermentation bed and its preparation method |
| CN112808759A (en) * | 2020-12-31 | 2021-05-18 | 河南省地质环境规划设计院有限公司 | Heavy metal polluted farmland restoration method |
Non-Patent Citations (1)
| Title |
|---|
| 黄伯云等, 山西科学技术出版社 * |
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