Heavy metal chromium contaminated soil remediation method

Abstract

The invention provides a heavy metal chromium contaminated soil remediation method which comprises the following steps: performing soil loosening treatment on a soil part needing to be remediated through a tractor or other machines, controlling a scarifier through a control unit, performing complete soil loosening treatment on the surface of soil, and driving a soil remediation device to move through a moving unit. Soil remediation operation is carried out on the surface of soil, multiple groups of filter bags for adsorbing high-molecular adsorbent particles of chromium are placed in the soil, clear water is pressurized and fed into the filter bags, and internal remediation treatment is carried out on the soil by means of the pumping principle through pressurized pumping work of a water pumping device; according to the remediation method, compacted soil is dug up and loosened, remediation use of the soil is facilitated, the soil remediation device is driven by the moving unit to move, all procedures are sequentially completed from front to back, and the remediation rate of the contaminated soil is greatly increased; the soil is further subjected to radiation treatment through the radiator, so that the remediation effect is improved.

Description

Technical Field

[0001] The invention relates to the field of soil remediation, and in particular to a method for remediating soil contaminated by heavy metal chromium. Background Art

[0002] After heavy metals enter the soil, they form different chemical forms through various reactions such as dissolution, precipitation, coagulation, complexation and adsorption, and show different activities. The form of heavy metals in the soil affects its activity and effectiveness to plants. Therefore, studying the forms of heavy metals in the soil and the transformation between forms is of great significance to the environmental effects of heavy metals and the treatment and restoration of heavy metal-contaminated soils. Various forms of heavy metals have different redistribution characteristics. Generally, exchangeable heavy metals in the soil have relatively strong biological activity, while residual heavy metals under natural conditions are not easily released from soil particles due to their strong binding force with soil minerals, and have low biological activity.

[0003] In general, the remediation method is to plant bald thorn flower in soil or sludge contaminated by heavy metals. This method utilizes the enrichment characteristics of bald thorn flower for four heavy metals, Cd, Cu, Pb, and Zn, and plants it in mining soil and sludge to absorb and accumulate Cd, Cu, Pb, and Zn, and transport most of them to the above-ground part, so as to achieve the purpose of repairing heavy metal pollution in mining soil and sludge. This remediation method is not effective and takes a long time to repair. Therefore, the present invention proposes a method for repairing heavy metal chromium contaminated soil to solve the problems existing in the prior art. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a method for remediating soil contaminated by heavy metal chromium, the method for remediating soil contaminated by heavy metal chromium.

[0005] The technical solution of the present invention is achieved as follows: A method for remediating soil contaminated by heavy metal chromium comprises the following steps;

[0006] Step 1: Use a tractor or other machinery to loosen the soil in the area that needs to be repaired, control the loosening device through the control unit, completely loosen the soil surface, and then use the mobile unit to drive the soil repair device to move and perform soil repair operations on the soil surface;

[0007] Step 2: Place multiple groups of filter bags containing polymer adsorbent particles for chromium adsorption inside the soil, pressurize and pump clean water into the filter bags, and use the pumping principle to perform internal repair on the soil through the pressurized suction work of the pumping device;

[0008] Step 3: Irradiate with gamma rays, the amount of radiation is determined by the area of ​​soil to be repaired;

[0009] Step 4: Preliminary spraying of the soil obtained after the radiation treatment in step 3, the spraying time is not less than 30 minutes, and the preliminary spraying liquid is a sodium polyepoxysuccinate solution;

[0010] Step 5: After the tiller in step 1 is completed, the soil remediator is controlled to move, iron filings, ethanol and other remediation materials are poured into the soil remediator before it moves to the soil, and then the soil remediator is evenly sprinkled on the heavy metal chromium contaminated soil to be remediated to perform remediation work. The iron filings are in a powdery structure, and the amount of remediation materials poured in is determined according to the area of ​​the soil to be remediated;

[0011] Step 6: Take out the filter bag in step 2, wash off the surface sand with water, and then perform desorption operation. The desorption liquid is placed in a recovery box for recycling;

[0012] Step 7: The repaired soil is tested by the detection unit, and the work of step 5 is repeated for the soil that fails the test until the repair is completed.

[0013] A further improvement is that in step one, the soil scarifier loosens the contaminated soil to prepare for subsequent restoration, and the soil is loosened by drilling through the soil scarifier's control unit.

[0014] A further improvement is that in step one, the mobile unit is a mobile vehicle or a special cart for the land, and the soil remediator is a material stirring mechanism and a material ejecting mechanism. By moving the mobile unit to the top of the soil, the soil remediator is controlled to mix multiple substances and then introduce them into the soil for remediation.

[0015] The further improvement is that in step 2, the filter bag is an ordinary filter bag on the market, and the polymer adsorbent is prepared by weighing a certain amount of konjac powder according to demand, dissolving it in distilled water, stirring it evenly to form a sol, and then adding an inorganic alkali aqueous solution and stirring it evenly. After the end, the sol is cooled and allowed to stand, and then the sol after standing is transferred to a sand core funnel, filtered and then washed with methanol, dried, and vacuum dried to obtain polymer adsorbent particles. The pumping device is a water pump, and the heavy metal chromium inside the soil is adsorbed through the suction treatment of the water pump.

[0016] Further improvement is that in step three, the gamma ray used is a strong electromagnetic wave. In nuclear reactions, when the nucleus decays, it often decays to an excited state. The nucleus in the excited state is still unstable and will release a series of energy to make it transition to a stable state. The release of this energy is achieved through ray radiation. This ray is gamma ray, which destroys the heavy metals inside the soil through gamma ray.

[0017] A further improvement is that in step 4, the irradiated soil is sprayed with a sodium polyepoxysuccinate solution, the sodium polyepoxysuccinate solution is concentrated by passing through an ether centrifuge to obtain an extract paste, and the extract paste is dissolved with an ethanol solution to obtain a sodium polyepoxysuccinate solution.

[0018] A further improvement is that in step five, iron filings, ethanol and other repair materials are poured into the soil repair device and mixed and stirred. After the mixing is completed, the materials are placed on the soil surface through the soil repair device to remove chromium pollution on the soil surface.

[0019] Further improvement is: in step six, the filter bag is taken out, and the filter bag is taken out after the repair is completed. The soil inside the filter bag is repaired, the soil on the surface of the taken out filter bag is removed, and then the filter bag is placed in a safe recycling box. The desorption operation in the recycling box is to use a desorption liquid for desorption treatment. The desorption liquid is a phosphoric acid solution, and the desorption temperature is forty degrees. After the desorption of the filter bag is completed, it is loaded with a polymer adsorbent again for use.

[0020] Further improvement is: in step seven, after completing all the repair work, the staff will test the repaired soil. The soil that passes the test does not need to be repaired further, while the soil that fails the test continues to be repaired. The detection method is to test the chromium pollution index inside the soil.

[0021] A further improvement is that in step 1, the soil is loosened before the soil is repaired in order to quickly carry out the repair work, and the loosener is a common shovel or tractor on the market.

[0022] Compared with the prior art, the present invention has the following advantages: the repair method digs up and loosens the compacted soil, making it easier to repair the soil; the soil repair device is driven by a mobile unit to complete each process from front to back, greatly improving the repair rate of the contaminated soil; the soil is further irradiated by a radiator to improve the repair effect; the filter bag is placed inside the soil, and external radiation treatment is added to repair the inside and outside of the soil at the same time, greatly improving the repair effect; the treatment liquid is fully and evenly sprinkled into the contaminated soil in the form of a spray, and the treatment liquid is fully contacted and reacted with the contaminated soil, making the soil repair work more comprehensive and suitable for large-scale soil repair. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Figure 1 It is the work flow chart of the present invention. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms installation, connection, and connection should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] See also Figure 1 , the embodiment of the present invention discloses a method for remediating soil contaminated by heavy metal chromium, comprising the following steps;

[0028] Step 1: Use a tractor or other machinery to loosen the soil in the area that needs to be repaired, control the loosening device through the control unit, completely loosen the soil surface, and then use the mobile unit to drive the soil repair device to move and perform soil repair operations on the soil surface;

[0029] Step 2: Place multiple groups of filter bags containing polymer adsorbent particles for chromium adsorption inside the soil, pressurize and pump clean water into the filter bags, and use the pumping device to perform the first soil repair treatment by using the suction principle;

[0030] Step 3: Irradiate with gamma rays, the amount of radiation is determined by the area of ​​soil to be repaired;

[0031] Step 4: Preliminary spraying of the soil obtained after the radiation treatment in step 3, the spraying time is not less than 30 minutes, and the preliminary spraying liquid is a sodium polyepoxysuccinate solution;

[0032] Step 5: After the tiller in step 1 is completed, the soil remediator is controlled to move, iron filings, ethanol and other remediation materials are poured into the soil remediator before it moves to the soil, and then the soil remediator is evenly sprinkled on the heavy metal chromium contaminated soil to be remediated to perform remediation work. The iron filings are in a powdery structure, and the amount of remediation materials poured in is determined according to the area of ​​the soil to be remediated;

[0033] Step 6: Take out the filter bag in step 2, wash off the surface sand with water, and then perform desorption operation. The desorption liquid is placed in a recovery box for recycling;

[0034] Step 7: The repaired soil is tested by the detection unit, and the work of step 5 is repeated for the soil that fails the test until the repair is completed.

[0035] In step one, the soil scarifier loosens the contaminated soil in preparation for subsequent remediation, and the soil is loosened by drilling into the ground through the control unit of the soil scarifier.

[0036] In step one, the mobile unit is a mobile vehicle or a special cart for the land, and the soil remediator is a material stirring mechanism and a material ejecting mechanism. By moving the mobile unit to the top of the soil, the soil remediator is controlled to mix a variety of materials and then introduce them into the soil for remediation.

[0037] In step 2, the filter bag is an ordinary filter bag on the market, and the polymer adsorbent is prepared by weighing a certain amount of konjac powder according to demand, dissolving it in distilled water, stirring it evenly to form a sol, and then adding an inorganic alkali aqueous solution and stirring it evenly. After the end, the sol is cooled and allowed to stand, and then the sol after standing is transferred to a sand core funnel, filtered and then washed with methanol, dried, and vacuum dried to obtain polymer adsorbent particles. The pumping device is a water pump, and the heavy metal chromium inside the soil is adsorbed through the suction treatment of the water pump.

[0038] In step three, the gamma rays used are a kind of strong electromagnetic waves. In nuclear reactions, when the nucleus decays, it often decays to an excited state. The nucleus in the excited state is still unstable and will release a series of energy to make it transition to a stable state. The release of this energy is achieved through ray radiation. This ray is gamma rays, which destroy the heavy metals inside the soil.

[0039] In step 4, the irradiated soil is sprayed with a sodium polyepoxysuccinate solution, and the following raw materials are weighed in weight fraction for preparation: 10 parts of rice bran, 40 parts of bean dregs, 8 parts of straw, and 11 parts of rape stalks, and then each raw material is crushed by a pulverizer and ground into powder; a certain amount of the above powder is added to a certain volume of ether, stirred evenly, and soaked in a water bath at a temperature of 50-60° C. for twelve hours; microwave treatment is then performed: the ether extract subjected to the leaching treatment is subjected to microwave treatment, the microwave treatment time is 30-50 minutes, and the treatment temperature is 55° C.; a standing treatment is then performed: the ether extract after the microwave treatment is soaked at room temperature for 1 to 2 days; the soaking solution is centrifuged in a low-speed centrifuge for 10 minutes; the ether centrifuge liquid through which the sodium polyepoxysuccinate solution passes is concentrated to obtain an extract paste, and the extract paste is dissolved in an ethanol solution to obtain a sodium polyepoxysuccinate solution.

[0040] In step five, iron filings, ethanol and other repair materials are poured into the soil repair device and mixed and stirred. After the mixing is completed, the materials are placed on the soil surface through the soil repair device to remove chromium pollution on the soil surface.

[0041] In step six, the filter bag is taken out after the repair is completed, and the soil inside the filter bag is repaired. The soil on the surface of the taken out filter bag is removed, and then the filter bag is placed in a safe recycling box. The desorption operation in the recycling box is to desorb with a desorption liquid. The desorption liquid is a phosphoric acid solution, and the desorption temperature is forty degrees. After the desorption of the filter bag is completed, it is loaded with a polymer adsorbent again for use.

[0042] In step seven, after completing all the repair work, the staff will test the repaired soil. Soil that passes the test does not need to be repaired further, while soil that fails the test will continue to be repaired. The detection method is to test the chromium pollution index inside the soil.

[0043] In step 1, the soil is loosened before the soil is repaired in order to quickly carry out the repair work. The loosener is a common shovel or tractor on the market.

[0044] When the heavy metal chromium contaminated soil remediation method is used, the soil part to be repaired is loosened by a tractor or other machinery, and irradiated with gamma rays. The radiation amount is determined according to the area of ​​soil to be repaired, and then the soil remediator is evenly sprinkled on the heavy metal chromium contaminated soil to be repaired for remediation. The filter bag is an ordinary filter bag on the market. The polymer adsorbent is prepared by weighing a certain amount of konjac powder according to demand, dissolving it in distilled water, stirring it evenly to form a sol, and then adding an inorganic alkali aqueous solution and stirring it evenly. After the end, the sol is cooled and allowed to stand, and then the sol after standing is transferred to a sand core funnel, filtered and then washed with methanol, dried, and vacuum dried to obtain polymer adsorbent particles. The gamma rays used are a strong electromagnetic wave. In a nuclear reaction, when the nucleus decays, it often decays to a certain excited state and is in an excited state. The atomic nucleus in the state is still unstable, and it will transition to a stable state by releasing a series of energy, and the release of this energy is achieved through radiation. This type of ray is gamma rays, which destroy the heavy metals inside the soil and are taken out through the filter bag. The filter bag is taken out after the repair is completed. The soil inside the filter bag is repaired, and the soil on the surface of the taken out filter bag is removed, and then the filter bag is placed in a safe recycling box. The desorption operation in the recycling box is to desorb with a desorption liquid. The desorption liquid is a phosphoric acid solution, and the desorption temperature is forty degrees. After the desorption of the filter bag is completed, it is re-loaded with a polymer adsorbent for use. The staff will test the repaired soil. The soil that passes the test does not need to be repaired, and the soil that fails the test continues to be repaired. The detection method is to test the chromium pollution index inside the soil.

[0045] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for remediating soil contaminated by heavy metal chromium, characterized in that: The steps include: Step 1: The control unit controls the soil loosener to completely loosen the soil surface, and then the mobile unit drives the soil remediator to move to perform soil remediation operations on the soil surface; Step 2: Place multiple groups of filter bags containing polymer adsorbent particles for chromium adsorption inside the soil, pressurize and pump clean water into the filter bags, and use the pumping device to perform the first soil repair treatment by using the suction principle; Step 3: by irradiation with gamma rays; Step 4: Preliminary spraying of the soil obtained after the radiation treatment in step 3, the spraying time is not less than 30 minutes, and the preliminary spraying liquid is a sodium polyepoxysuccinate solution; Step 5: After the tiller in step 1 is finished, the soil repairer is controlled to move, and before the soil repairer moves to the soil, iron filings, ethanol and other repair substances are poured into the soil repairer. The iron filings are in a powdery structure, and the amount of the repair substance poured in is determined according to the area of ​​the soil to be repaired; Step 6: Take out the filter bag in step 2, wash off the surface sand with water, and then perform desorption operation. The desorption liquid is placed in a recovery box for recycling; Step 7: The repaired soil is tested by the detection unit, and the work of step 5 is repeated for the soil that fails the test until the repair is completed.

2. The method for remediating soil contaminated by heavy metal chromium according to claim 1, characterized in that: In the step 1, the soil scarifier loosens the contaminated soil to prepare for subsequent restoration, and the soil is loosened by drilling through the soil scarifier's control unit.

3. The method for remediating soil contaminated by heavy metal chromium according to claim 1, characterized in that: In step one, the mobile unit is a mobile vehicle or a special cart for the land, and the soil remediator is a material stirring mechanism and a material ejecting mechanism. By moving the mobile unit to the top of the soil, the soil remediator is controlled to mix a variety of materials and then introduce them into the soil for remediation.

4. The method for remediating soil contaminated by heavy metal chromium according to claim 1, characterized in that: In the step 2, the filter bag is a common filter bag on the market, and the pumping device is a water pump. The heavy metal chromium inside the soil is adsorbed through the suction treatment of the water pump.

5. The method for remediating soil contaminated by heavy metal chromium according to claim 1, characterized in that: In step three, gamma rays are used to destroy heavy metals in the soil.

6. The method for remediating soil contaminated by heavy metal chromium according to claim 1, characterized in that: In the step 4, the irradiated soil is sprayed with a sodium polyepoxysuccinate solution, the sodium polyepoxysuccinate solution is concentrated by ether centrifuge to obtain an extract paste, and the extract paste is dissolved with an ethanol solution to obtain a sodium polyepoxysuccinate solution.

7. The method for remediating soil contaminated by heavy metal chromium according to claim 1, characterized in that: In step five, iron filings, ethanol and other repair materials are poured into the soil repair device and mixed and stirred. After the mixing is completed, the materials are placed on the soil surface through the soil repair device to remove chromium pollution on the soil surface.

8. The method for remediating soil contaminated by heavy metal chromium according to claim 1, characterized in that: In step six, the filter bag is taken out after the repair is completed, and the filter bag is subjected to adsorption and desorption treatment. After the desorption of the filter bag is completed, the polymer adsorbent is loaded into the filter bag again for use.

9. The method for remediating soil contaminated by heavy metal chromium according to claim 1, characterized in that: In step seven, after all the repair work is completed, the repaired soil is tested by the staff. The soil that passes the test does not need to be repaired, while the soil that fails the test continues to be repaired. The detection method is to test the chromium pollution index inside the soil.

10. The method for remediating soil contaminated by heavy metal chromium according to claim 1, characterized in that: In the step 1, the soil is loosened before repairing the soil in order to quickly carry out the repair work and accelerate the repair rate. The loosening device is a common shovel on the market.

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