A method of soil restoration

Abstract

The invention discloses a soil remediation method. The method specifically comprises the following process that step 1, soil with 60 cm deep at a polluted place is scooped up; step 2, the polluted soil which is scooped up is uniformly mixed with modified cyclodextrin, and pretreated polluted soil is obtained; step 3, the pretreated polluted soil is poured into a soil pit paved with composite barrier powder, then a certain amount of leaching agent is sprayed to the surface of the pretreated polluted soil, three days leaching reaction is carried out after spraying, then second spraying is carried out, and ten days leaching reaction is carried out after the second spraying; and step 4, a repairing agent is sprayed on the surface of the polluted soil treated in the step 3, and curing is carried out three to five days after spraying. According to the soil remediation method, the modified cyclodextrin is directly mixed with the polluted soil, adsorption and fixation of heavy metal ions and pesticide pollutants can be realized through the modified cyclodextrin, so that the problems that the existing heavy metal treating agent can only be used for adsorbing heavy metals, the absorption ofthe organic pesticide pollutants need to be additionally added with an adsorbent, the remediation cost is high, and the treatment process is complex are solved.

Description

technical field

[0001] The invention belongs to the field of soil restoration and relates to a soil restoration method. Background technique

[0002] In recent years, due to the discharge of factory sewage and the unreasonable use of pesticides, the content of heavy metal ions and organic toxic pollutants in the soil has exceeded the standard. Under the immersion of long-term rainwater, heavy metal ions and organic toxic pollutants seep into the groundwater and enter the drinking water of residents through the groundwater. In the process, the quality of drinking water is not up to standard and endangers human health.

[0003] Existing soil remediation agents mainly use biological action or chemical solidification, and the solidified heavy metal ions are still easy to migrate to the underlying soil, causing secondary pollution. At the same time, the existing soil remediation agents are directly mixed with the soil to be remediated Adsorption and fixation are carried out. Bef...

Examples

Embodiment 1

[0031] The preparation process of the composite barrier powder is as follows:

[0032] Step 1: Add 1kg of starch to 2L of water to make a starch solution;

[0033] Step 2: Add 150g of sodium periodate to the starch solution, raise the temperature to 50°C and stir for 1 hour, then add 50mL of ethylene glycol to remove unreacted sodium periodate, then wash with ethanol and dry to obtain oxidized ring-opened starch;

[0034] Step 3: Add 900g of the oxidized ring-opened starch prepared in step 2 into 31.5L of water and mix evenly, add 10.8kg of fly ash into it, stir and mix thoroughly for 30min, then raise the temperature to 60°C, and add 2.7 L thiourea solution, wherein the thiourea solution is prepared by dissolving each gram of thiourea in 8 mL of water, stirring vigorously while adding dropwise, keeping 8-9 mL dropwise per minute, and reacting at a constant temperature for 3 hours after the dropwise addition, and then filtering and washing. The obtained product is ground to ...

Embodiment 2

[0040] The preparation process of the composite barrier powder is as follows:

[0041] Step 1: Add 1kg of starch to 2L of water to make a starch solution;

[0042] Step 2: Add 160g of sodium periodate to the starch solution, raise the temperature to 50°C and stir for 1 hour, then add 50mL of ethylene glycol to remove unreacted sodium periodate, then wash with ethanol and dry to obtain oxidized ring-opened starch;

[0043] Step 3: Add 900g of the oxidized ring-opened starch prepared in step 2 into 31.5L of water and mix evenly, add 11.7kg of fly ash to it, stir and mix thoroughly for 30min, then raise the temperature to 60°C, and add 2.7kg of L thiourea solution, wherein the thiourea solution is prepared by dissolving each gram of thiourea in 8 mL of water, stirring vigorously while adding dropwise, keeping 8-9 mL dropwise per minute, and reacting at a constant temperature for 3 hours after the dropwise addition, and then filtering and washing. The obtained product is ground ...

Embodiment 3

[0049] A method for soil restoration, specifically comprising the following processes:

[0050] In the first step, the soil in the polluted area is scooped up to a depth of 60 cm, and at the same time, a layer of composite barrier powder prepared in Example 1 is laid in the scooped-up soil pit, wherein the laying thickness is 1-1.2 cm;

[0051] In the second step, the scooped-up polluted soil is evenly mixed with the modified cyclodextrin prepared in Example 1 to obtain the pre-treated polluted soil. In the polluted soil with a total heavy metal content of 0.5-2%, every kilogram of heavy metal polluted soil is added Modified cyclodextrin 11-13g;

[0052] The third step is to pour the pretreated contaminated soil into the pit where the composite barrier powder is laid, and then spray a certain amount of leaching agent on the surface of the pretreated contaminated soil. Post-leaching reaction for 10 days, then spraying for the third time, leaching reaction after spraying for 20...

technical field

[0001] The invention belongs to the field of soil restoration and relates to a soil restoration method. Background technique

[0002] In recent years, due to the discharge of factory sewage and the unreasonable use of pesticides, the content of heavy metal ions and organic toxic pollutants in the soil has exceeded the standard. Under the immersion of long-term rainwater, heavy metal ions and organic toxic pollutants seep into the groundwater and enter the drinking water of residents through the groundwater. In the process, the quality of drinking water is not up to standard and endangers human health.

[0003] Existing soil remediation agents mainly use biological action or chemical solidification, and the solidified heavy metal ions are still easy to migrate to the underlying soil, causing secondary pollution. At the same time, the existing soil remediation agents are directly mixed with the soil to be remediated Adsorption and fixation are carried out. Bef...

Examples

Embodiment 1

[0031] The preparation process of the composite barrier powder is as follows:

[0032] Step 1: Add 1kg of starch to 2L of water to make a starch solution;

[0033] Step 2: Add 150g of sodium periodate to the starch solution, raise the temperature to 50°C and stir for 1 hour, then add 50mL of ethylene glycol to remove unreacted sodium periodate, then wash with ethanol and dry to obtain oxidized ring-opened starch;

[0034] Step 3: Add 900g of the oxidized ring-opened starch prepared in step 2 into 31.5L of water and mix evenly, add 10.8kg of fly ash into it, stir and mix thoroughly for 30min, then raise the temperature to 60°C, and add 2.7 L thiourea solution, wherein the thiourea solution is prepared by dissolving each gram of thiourea in 8 mL of water, stirring vigorously while adding dropwise, keeping 8-9 mL dropwise per minute, and reacting at a constant temperature for 3 hours after the dropwise addition, and then filtering and washing. The obtained product is ground to ...

Embodiment 2

[0040] The preparation process of the composite barrier powder is as follows:

[0041] Step 1: Add 1kg of starch to 2L of water to make a starch solution;

[0042] Step 2: Add 160g of sodium periodate to the starch solution, raise the temperature to 50°C and stir for 1 hour, then add 50mL of ethylene glycol to remove unreacted sodium periodate, then wash with ethanol and dry to obtain oxidized ring-opened starch;

[0043] Step 3: Add 900g of the oxidized ring-opened starch prepared in step 2 into 31.5L of water and mix evenly, add 11.7kg of fly ash to it, stir and mix thoroughly for 30min, then raise the temperature to 60°C, and add 2.7kg of L thiourea solution, wherein the thiourea solution is prepared by dissolving each gram of thiourea in 8 mL of water, stirring vigorously while adding dropwise, keeping 8-9 mL dropwise per minute, and reacting at a constant temperature for 3 hours after the dropwise addition, and then filtering and washing. The obtained product is ground ...

Embodiment 3

[0049] A method for soil restoration, specifically comprising the following processes:

[0050] In the first step, the soil in the polluted area is scooped up to a depth of 60 cm, and at the same time, a layer of composite barrier powder prepared in Example 1 is laid in the scooped-up soil pit, wherein the laying thickness is 1-1.2 cm;

[0051] In the second step, the scooped-up polluted soil is evenly mixed with the modified cyclodextrin prepared in Example 1 to obtain the pre-treated polluted soil. In the polluted soil with a total heavy metal content of 0.5-2%, every kilogram of heavy metal polluted soil is added Modified cyclodextrin 11-13g;

[0052] The third step is to pour the pretreated contaminated soil into the pit where the composite barrier powder is laid, and then spray a certain amount of leaching agent on the surface of the pretreated contaminated soil. Post-leaching reaction for 10 days, then spraying for the third time, leaching reaction after spraying for 20...

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