CN110653256A - Treatment method of heavy metal contaminated soil - Google Patents
Treatment method of heavy metal contaminated soil Download PDFInfo
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- CN110653256A CN110653256A CN201911088120.0A CN201911088120A CN110653256A CN 110653256 A CN110653256 A CN 110653256A CN 201911088120 A CN201911088120 A CN 201911088120A CN 110653256 A CN110653256 A CN 110653256A
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- treatment
- soil
- grass
- heavy metal
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B09—DISPOSAL OF SOLID WASTE; RECLAMATION OF CONTAMINATED SOIL
- B09C—RECLAMATION OF CONTAMINATED SOIL
- B09C1/00—Reclamation of contaminated soil
- B09C1/10—Reclamation of contaminated soil microbiologically, biologically or by using enzymes
- B09C1/105—Reclamation of contaminated soil microbiologically, biologically or by using enzymes using fungi or plants
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B09—DISPOSAL OF SOLID WASTE; RECLAMATION OF CONTAMINATED SOIL
- B09C—RECLAMATION OF CONTAMINATED SOIL
- B09C1/00—Reclamation of contaminated soil
- B09C1/08—Reclamation of contaminated soil chemically
- B09C1/085—Reclamation of contaminated soil chemically electrochemically, e.g. by electrokinetics
Abstract
The invention discloses a method for treating heavy metal contaminated soil, and belongs to the field of soil treatment. A treatment method of heavy metal contaminated soil comprises the following steps: the first step is as follows: selecting a certain area near the polluted soil area, and excavating a treatment pit; the second step is that: laying isolation films on the bottom side and the periphery of the pit; the third step: laying rows of water return pipes with certain height after laying the isolating membranes, and then installing a filter box, a treatment box, a circulating pump, a dosing box and a spraying pipe connected with the dosing box, wherein the filter box, the treatment box, the circulating pump and the dosing box are sequentially connected with the water return pipes; the spraying pipe sprays the treated water pumped by the circulating pump onto the ciliate desert-grass and the duckweed, so that the ciliate desert-grass and the duckweed can grow, the adsorption and purification effects on heavy metal ions are improved, in addition, the arsenic-resistant bacteria sprayed and carried in the dosing box can flow into the root of the ciliate desert-grass, the arsenic-resistant bacteria can stimulate the growth of the ciliate desert-grass to a certain degree, and the overall treatment effect is good.
Description
Technical Field
The invention relates to the technical field of soil treatment, in particular to a method for treating heavy metal contaminated soil.
Background
The heavy metal pollution of the soil refers to pollution caused by excessive accumulation of heavy metals in the soil, and the heavy metals in the polluted soil comprise elements with remarkable biological toxicity, such as cadmium, lead, mercury, chromium and arsenic, and elements with certain toxicity, such as copper, zinc and nickel. The method has the advantages that the pollution range is wide, the duration is long, the pollution is hidden and cannot be biologically degraded, the soil degradation is greatly caused, the crop yield and the crop quality are reduced, the surface water and the underground water are polluted by runoff and leaching loss, excessive heavy metals have adverse effects on the physiological functions of the plants, the nutrition imbalance of the plants pollutes the surface water and the underground water, the excessive heavy metals have adverse effects on the physiological functions of the plants, the nutrition imbalance of the plants is realized, the mercury and the arsenic can inhibit the activities of nitrifying and ammoniating bacteria in the soil and block the nitrogen supply, the heavy metals can be enriched through a food chain and generate methyl compounds with stronger toxicity to poison the food chain organisms, and finally the heavy metals are accumulated in a human body and harm the human health, so that the method is very important for treating the soil polluted by the heavy metals and ensuring.
Disclosure of Invention
The invention aims to solve the problems in the prior art and provides a method for treating heavy metal contaminated soil.
In order to achieve the purpose, the invention adopts the following technical scheme:
a treatment method of heavy metal contaminated soil comprises the following steps:
the first step is as follows: selecting a certain area near the polluted soil area, and excavating a treatment pit;
the second step is that: laying isolation films on the bottom side and the periphery of the pit;
the third step: laying rows of water return pipes with certain height after laying the isolating membranes, and then installing a filter box, a treatment box, a circulating pump, a dosing box and a spraying pipe connected with the dosing box, wherein the filter box, the treatment box, the circulating pump and the dosing box are sequentially connected with the water return pipes;
the fourth step: digging the heavy metal polluted soil to be treated into a treatment pit and uniformly paving the soil;
the fifth step: clean water is conveyed into the treatment pit by using a circulating pump;
and a sixth step: after the treatment pit is completely filled with water in the treatment pit, planting ciliate desert-grass and duckweed on the water surface in the treatment pit;
the seventh step: soaking the water in the treatment pit for one day;
eighth step: starting a circulating pump after soaking for one day, slowly extracting water soaked in the soil by using a water return pipe, and spraying the water onto the ciliate desert-grass and the duckweed through a spraying pipe to form a spraying circulating system;
ninth, adding a certain amount of arsenic-resisting bacteria into a medicine adding box, and spraying the arsenic-resisting bacteria onto the ciliate desert-grass and flowing into the root of the ciliate desert-grass during spraying;
the tenth step: and (3) carrying out circulating spraying for 10-12 days, discharging water in the treatment pit after 10-12 days, taking out the planted floating ciliate desert-grass and duckweed, taking out the treated soil and transporting the treated soil back to the original place, and then transporting the new heavy metal polluted soil into the treatment pit for continuous treatment by repeating the steps.
Preferably, ciliate desert-grass and duckweed plant through planting the layer the processing hole on, the planting layer is including adsorbing basic unit, disintegrating slag intermediate level and the basal soil layer that is mingled with the showy board, ciliate desert-grass plant on basic soil layer just ciliate desert-grass part root insert in the disintegrating slag intermediate level, the root of duckweed alternate basal soil layer be arranged in adsorbing basic unit and/disintegrating slag intermediate level and/water layer.
Preferably, the adsorption base layer is mainly formed by combining humic acid and chitosan resin, and the humic acid, the chitosan resin and the mixed floating plates are stably bound through a binding net.
Preferably, the slag crushing middle layer is made of halloysite.
Preferably, the pit is excavated in the first step by stacking a weir around the treatment pit and laying the barrier film such that an upper end of the barrier film passes over the weir.
Preferably, a filter sleeve is sleeved outside the water return pipe in the third step, and the filter sleeve mainly comprises an inner net layer, an outer net layer and an intermediate layer clamped with sponge.
Preferably, the filter box in the third step is a reverse osmosis filter, and the treatment box is an electrodialysis processor.
Preferably, in the fourth step, the soil is transported to the treatment pit and spread evenly, and the soil is spread evenly through the screen.
Preferably, when the ninth step of continuous cyclic spraying is carried out, a certain amount of arsenic-resistant bacteria needs to be added into the dosing tank in real time, and water needs to be supplemented into the treatment pit to ensure the water level in the treatment pit.
Compared with the prior art, the invention provides a method for treating heavy metal contaminated soil, which has the following beneficial effects:
1. the method for treating the soil polluted by the heavy metal comprises the steps of soaking the soil to be treated by clean water in a treatment pit during treatment, soaking heavy metal ions in the soil, starting a circulating pump, pumping water containing the heavy metal ions into a filter box and a treatment box by the circulating pump through a water return pipe for primary filtration and treatment of the heavy metal ions, effectively absorbing the heavy metal ions in the treatment pit by the planted ciliate desert-grass and duckweed to play a purifying role, spraying the treated water pumped by the circulating pump onto the ciliate desert-grass and the duckweed through a spraying pipe to facilitate the growth of the ciliate desert-grass and the duckweed, improving the adsorption and purification effects on the heavy metal ions, enabling arsenic-resistant bacteria sprayed and carried in a dosing box to flow into the root of the ciliate desert-grass, stimulating the growth of the ciliate desert-grass to a certain degree and improving the biomass of the ciliate desert-grass, in addition, E, G arsenic-resistant bacteria in the arsenic-resistant bacteria can enhance the arsenic absorption capacity of the ciliate desert-grass, promote the transfer of arsenic from the lower part of the ciliate desert-grass to the overground part, improve the growth conditions of the ciliate desert-grass, promote the growth and development of ciliate desert-grass root systems under the stress of arsenic, enlarge or prolong the contact area of the ciliate desert-grass root systems and polluted soil so as to enhance the absorption of ciliate desert-grass to the arsenic in the soil, improve the efficiency of soil adsorption, and have good overall treatment effect.
Drawings
FIG. 1 is a schematic view of a method for treating heavy metal contaminated soil according to the present invention;
FIG. 2 is a schematic view of a planting structure of ciliate desert-grass and duckweed of the treatment method of heavy metal contaminated soil according to the present invention;
FIG. 3 is a schematic view of a section structure of a water return pipe in the method for treating heavy metal contaminated soil according to the present invention.
In the figure: 1. an isolation film; 2. a water return pipe; 201. a mesh layer; 202. an intermediate layer sandwiched with sponge; 3. a filter box; 4. a treatment tank; 5. a circulation pump; 6. a dosing box; 7. a spray tube; 8. ciliate desert-grass; 9. duckweed; 10. a floating plate; 11. an adsorption base layer; 12. a slag intermediate layer; 13. a base soil layer; 14. and (6) bundling the net.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.
Referring to fig. 1 to 3, a method for treating heavy metal contaminated soil includes the steps of:
the first step is as follows: selecting a certain area near the polluted soil area, excavating a treatment pit, piling weirs around the treatment pit when the pit is excavated in the first step, and enabling the upper end of the isolation film 1 to cross the weirs when the isolation film 1 is laid;
the second step is that: laying isolation films 1 at the bottom side and the periphery of the pit;
the third step: laying a row of water return pipes 2 with certain height after laying the isolation films 1, and then installing a filter box 3, a treatment box 4, a circulating pump 5, a dosing box 6 and a spraying pipe 7 connected with the dosing box 6 which are sequentially connected with the water return pipes 2;
the fourth step: digging the heavy metal polluted soil to be treated into a treatment pit and uniformly paving the soil;
the fifth step: clean water is conveyed into the treatment pit by a circulating pump 5;
and a sixth step: after the treatment pit is completely filled with water in the treatment pit, planting ciliate desert-grass 8 and duckweed 9 on the water surface in the treatment pit;
the seventh step: soaking the water in the treatment pit for one day;
eighth step: after soaking for one day, starting a circulating pump 5, slowly extracting water soaked in the soil by using a water return pipe 2, and then spraying the water onto ciliate desert-grass 8 and duckweed 9 through a spraying pipe 7 to form a spraying circulating system;
ninth, a certain amount of arsenic-resisting bacteria is added into the medicine adding box 6, and the arsenic-resisting bacteria are sprayed on the ciliate desert-grass 8 and flow into the root of the ciliate desert-grass 8 during spraying;
the tenth step: carrying out circulating spraying for 10-12 days, discharging water in the treatment pit after 10-12 days, taking out the planted pteris vittata 8 and duckweed 9, taking out the treated soil and transporting the treated soil back to the original place, and then transporting the new heavy metal contaminated soil into the treatment pit for continuous treatment by repeating the steps;
during treatment, the soil to be treated is soaked by clean water in the treatment pit, heavy metal ions in the soil are soaked, then the circulating pump 5 is started, the circulating pump 5 pumps water with the heavy metal ions into the filter box 3 and the treatment box 4 through the water return pipe 2 to primarily filter and treat the heavy metal ions, in addition, the heavy metal ions in the treatment pit can be effectively absorbed and purified by the planted ciliate desert-grass 8 and the duckweed 9, in addition, the treated water pumped by the circulating pump 5 is sprayed onto the ciliate desert-grass 8 and the duckweed 9 through the spraying pipe 7, the growth of the ciliate desert-grass 8 and the duckweed 9 is facilitated, the adsorption and purification effect on the heavy metal ions is improved, in addition, the arsenic-resistant bacteria sprayed and carried in the dosing box 6 can flow into the root of the ciliate desert-grass 8, the growth of the ciliate desert-grass can be stimulated to a certain extent by the arsenic-resistant bacteria, and, in addition, E, G arsenic-resistant bacteria in the arsenic-resistant bacteria can enhance the arsenic absorption capacity of the ciliate desert-grass, promote the transfer of arsenic from the lower part of the ciliate desert-grass to the overground part, improve the growth conditions of the ciliate desert-grass, promote the growth and development of ciliate desert-grass root systems under the stress of arsenic, enlarge or prolong the contact area of the ciliate desert-grass root systems and polluted soil so as to enhance the absorption of ciliate desert-grass to the arsenic in the soil, improve the efficiency of soil adsorption, and have good overall treatment effect.
Ciliate desert-grass 8 and duckweed 9 are planted on the treatment pit through the planting layer, the planting layer comprises an adsorption base layer 11, a slag intermediate layer 12 and a base soil layer 13, the floating plate 10 is mixed with the adsorption base layer, the slag intermediate layer 12 and the base soil layer 13, the ciliate desert-grass 8 is planted on the base soil layer 13, part of the roots of the ciliate desert-grass 8 are inserted into the slag intermediate layer 12, the base soil layer 13 is inserted into the adsorption base layer 11 and/or the slag intermediate layer 12 and/or a water layer, and the ciliate desert-grass 8 and the duckweed 9 can be guaranteed to carry out effective absorption and purification treatment on heavy metal ions contained in.
The adsorption base layer 11 is mainly formed by combining humic acid and chitosan resin, the humic acid, the chitosan resin and the mixed floating plate 10 are stably bound through the binding net 14, and the humic acid and the chitosan resin can effectively adsorb heavy metal ions.
The slag intermediate layer 12 is made of halloysite which is irregular in shape, so that the ventilation effect of the root of the ciliate desert-grass 8 is ensured while heavy metal ions can be effectively absorbed, the growth of the ciliate desert-grass 8 is ensured, and the purification effect is ensured.
In the third step, a filter sleeve is sleeved outside the water return pipe 2, the filter sleeve mainly comprises an inner net layer 201, an outer net layer 201 and an intermediate layer 202 clamped with sponge, the water return pipe 2 can absorb the soaked water in the soil, and sundries are prevented from blocking a water inlet of the water return pipe 2.
In the third step, the filter box 3 is a reverse osmosis filter, and the treatment box 4 is an electrodialysis processor, so that reverse osmosis and electrodialysis treatment can be carried out, and heavy metal ions mixed in water can be effectively taken out.
In the fourth step, the soil is transported to the treatment pit and is uniformly paved, the soil is uniformly paved through the screen, the uniformity of the soil to be treated is ensured, the water can uniformly permeate into the soil after being uniformly paved, and meanwhile, the water return pipe 2 can conveniently return water to absorb the water.
When the ninth step is continuously and circularly sprayed, a certain amount of arsenic-resistant bacteria needs to be added into the dosing tank 6 in real time, and water needs to be added into the treatment pit to ensure the water level in the treatment pit.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (9)
1. The method for treating the heavy metal contaminated soil is characterized by comprising the following steps of:
the first step is as follows: selecting a certain area near the polluted soil area, and excavating a treatment pit;
the second step is that: laying isolation films (1) at the bottom side and the periphery of the pit;
the third step: paving rows of water return pipes (2) with certain height after paving the isolation films (1), and then installing a filter box (3), a treatment box (4), a circulating pump (5), a dosing box (6) and a spraying pipe (7) connected with the dosing box (6) which are sequentially connected with the water return pipes (2);
the fourth step: digging the heavy metal polluted soil to be treated into a treatment pit and uniformly paving the soil;
the fifth step: clean water is conveyed into the treatment pit by a circulating pump (5);
and a sixth step: after the treatment pit is completely filled with water in the treatment pit, planting ciliate desert-grass (8) and duckweed (9) on the water surface in the treatment pit;
the seventh step: soaking the water in the treatment pit for one day;
eighth step: after soaking for one day, starting a circulating pump (5), slowly extracting water soaked in the soil by using a water return pipe (2), and then spraying the water onto ciliate desert-grass (8) and duckweed (9) through a spraying pipe (7) to form a spraying circulating system;
ninth, adding a certain amount of arsenic-resisting bacteria into the medicine adding box (6), and spraying the arsenic-resisting bacteria onto the ciliate desert-grass (8) and flowing into the root of the ciliate desert-grass (8) during spraying;
the tenth step: and (3) carrying out circulating spraying for 10-12 days, discharging water in the treatment pit after 10-12 days, taking out the planted floating ciliate desert-grass (8) and duckweed (9), taking out the treated soil, transporting the treated soil back to the original place, and then transporting the new heavy metal contaminated soil into the treatment pit for continuous treatment by repeating the steps.
2. The method for treating the heavy metal contaminated soil according to claim 1, wherein the ciliate desert-grass (8) and the duckweed (9) are planted on the treatment pit through planting layers, the planting layers comprise an adsorption base layer (11) mixed with floating plates (10), a slag intermediate layer (12) and a base soil layer (13), the ciliate desert-grass (8) is planted on the base soil layer (13), part of roots of the ciliate desert-grass (8) are inserted into the slag intermediate layer (12), and the roots of the duckweed (9) are inserted into the base soil layer (13) and are located in the adsorption base layer (11), the slag intermediate layer (12) and/or a water layer.
3. The method for treating the heavy metal contaminated soil according to claim 2, wherein the adsorption base layer (11) is mainly formed by combining humic acid and chitosan resin, and the humic acid, the chitosan resin and the included floating plates (10) are bound and stabilized by a binding net (14).
4. A method for treating soil contaminated by heavy metals according to claim 2 or 3, wherein said intermediate layer of debris (12) is made of halloysite.
5. The method for treating heavy metal contaminated soil according to claim 1, wherein the pit is excavated in the first step by stacking a weir around the pit, and the isolating membrane (1) is laid such that the upper end of the isolating membrane (1) passes over the weir.
6. The method for treating heavy metal contaminated soil according to claim 1, wherein the water return pipe (2) in the third step is externally sleeved with a filter sleeve, and the filter sleeve mainly comprises an inner net layer (201), an outer net layer (201) and an intermediate layer (202) clamped with sponge.
7. The method for treating heavy metal contaminated soil according to claim 1 or 6, wherein the filtration tank (3) in the third step is a reverse osmosis filter, and the treatment tank (4) is an electrodialysis processor.
8. The method for treating heavy metal contaminated soil according to claim 1, wherein in the fourth step, the soil is transported to the treatment pit and spread uniformly, and the soil is spread uniformly through the screen.
9. The method for treating heavy metal contaminated soil according to claim 1, wherein a certain amount of arsenic-resistant bacteria is added to the dosing tank (6) in real time during the ninth step of continuous cyclic spraying, and water is supplemented to the treatment pit to ensure the water level in the treatment pit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201911088120.0A CN110653256A (en) | 2019-11-08 | 2019-11-08 | Treatment method of heavy metal contaminated soil |
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| CN201911088120.0A CN110653256A (en) | 2019-11-08 | 2019-11-08 | Treatment method of heavy metal contaminated soil |
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| CN201911088120.0A Withdrawn CN110653256A (en) | 2019-11-08 | 2019-11-08 | Treatment method of heavy metal contaminated soil |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111203439A (en) * | 2020-04-02 | 2020-05-29 | 袁伟伟 | Deep neutralization regeneration device for soil with over-standard pH value |
| CN111229824A (en) * | 2020-01-18 | 2020-06-05 | 昆明理工大学 | Method for restoring polycyclic aromatic hydrocarbon polluted soil by rush |
| CN111530910A (en) * | 2020-05-13 | 2020-08-14 | 徐州康卓化工设备有限公司 | Chemical pollution's deep soil prosthetic devices |
| CN113624755A (en) * | 2021-08-13 | 2021-11-09 | 九江学院 | Method for rapidly determining recovery effect of degraded soil |
-
2019
- 2019-11-08 CN CN201911088120.0A patent/CN110653256A/en not_active Withdrawn
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111229824A (en) * | 2020-01-18 | 2020-06-05 | 昆明理工大学 | Method for restoring polycyclic aromatic hydrocarbon polluted soil by rush |
| CN111229824B (en) * | 2020-01-18 | 2021-09-28 | 昆明理工大学 | Method for restoring polycyclic aromatic hydrocarbon polluted soil by rush |
| CN111203439A (en) * | 2020-04-02 | 2020-05-29 | 袁伟伟 | Deep neutralization regeneration device for soil with over-standard pH value |
| CN111530910A (en) * | 2020-05-13 | 2020-08-14 | 徐州康卓化工设备有限公司 | Chemical pollution's deep soil prosthetic devices |
| CN113624755A (en) * | 2021-08-13 | 2021-11-09 | 九江学院 | Method for rapidly determining recovery effect of degraded soil |
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Application publication date: 20200107 |