CN105598152A - Soil heavy metal pollution in-suit capturing treating method - Google Patents

Soil heavy metal pollution in-suit capturing treating method Download PDF

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Publication number
CN105598152A
CN105598152A CN201510742189.6A CN201510742189A CN105598152A CN 105598152 A CN105598152 A CN 105598152A CN 201510742189 A CN201510742189 A CN 201510742189A CN 105598152 A CN105598152 A CN 105598152A
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China
Prior art keywords
heavy metal
soil
trapping
pollution
original position
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CN201510742189.6A
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Chinese (zh)
Inventor
潘胜强
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深圳多元拓展环保科技有限公司
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Priority to CN201510742189.6A priority Critical patent/CN105598152A/en
Publication of CN105598152A publication Critical patent/CN105598152A/en

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B09DISPOSAL OF SOLID WASTE; RECLAMATION OF CONTAMINATED SOIL
    • B09CRECLAMATION OF CONTAMINATED SOIL
    • B09C1/00Reclamation of contaminated soil
    • B09C1/08Reclamation of contaminated soil chemically
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B09DISPOSAL OF SOLID WASTE; RECLAMATION OF CONTAMINATED SOIL
    • B09CRECLAMATION OF CONTAMINATED SOIL
    • B09C2101/00In situ

Abstract

The invention discloses a soil heavy metal pollution in-suit capturing treating method. The soil heavy metal pollution in-suit capturing treating method comprises following steps: 1) a heavy metal capturing agent is packaged with a permeable device; 2) the permeable device is buried in water-containing polluted soil; 3) the time of the permeable device buried in water-containing polluted soil is determined based on requirements, wherein when the permeable device is buried in soil aqueous solution, reactions such as ion exchange, ion complexation, and ion absorption of heavy metal ions in soil aqueous solution with the heavy metal capturing agent are realized via concentration diffusion, and the heavy metal ions are captured; and 4) the permeable device buried in soil is removed, and the heavy metal capturing agent is removed after capturing heavy metal, so that the heavy metal elements in soil are removed. The soil heavy metal pollution in-suit capturing treating method is capable of removing heavy metal capturing products effectively; operation is simple; soil physicochemical properties are not influenced; soil ecological functions are maintained; no secondary environmental risk is caused; treatment effect is excellent; and cost is low.

Description

A kind of heavy metal pollution of soil original position trapping improvement method

Technical field

The invention belongs to heavy metal pollution of soil and administer field, be specifically related to a kind of heavy metal pollution of soil original position trapping and controlReason method.

Background technology

Soil is an Open Dynamic system that complexity is heterogeneous, mainly comprises solid phase, liquid phase, gas phase and biofacies. SoilEcological functions are that material connects each other in soil heterogeneous system, the embodiment of the dynamic process of restriction mutually. Institute in solid phase of soilThe a large amount of clay minerals that contain and organic matter etc., effectively sticking enters the various pollution factors of its inside, and then sends out in soilRaw accumulation, when accumulation exceedes when a certain amount of, soil system output will be detrimental to health directly or indirectly, i.e. soil dirtDye.

China's heavy metal pollution of soil situation is quite severe. According to Ministry of Agriculture's statistics, the soil face of China's heavy metal pollutionAmass and reached up to ten million hectares, more than accounting for the l0% of total cultivated area, majority concentrates on the area that economy is more flourishing. The whole nation is subject to every yearThe grain of heavy metal pollution reaches 1.2 × 107Ton, because heavy metal pollution causes grain drop in production up to 107Ton, amounts to economic damageLose at least 200 hundred million yuan. Heavy metal pollution of soil become be related to economy especially agricultural sustainable development and healthGreat environmental problem, cause social concerns widely.

Farmland, Heavy Metal Pollution In Cultivated Land are administered and first should be considered that heavy metal element exists form in soil.The researchs such as Tessier think that heavy metal element is mainly divided into water-soluble state, exchange state, carbonate in conjunction with state, ferrimanganic oxygen in soilCompound is in conjunction with state, combination state and residual. The research of heavy metal pollution of soil risk transmission shows: water-soluble state, exchange stateBe the risk source the most easily transmitting with organically combining state heavy metal, these three kinds of form heavy metal elements are easily by bio-absorbable, absorptionAnd accumulation etc., produce environmental risk effect; Next is carbonate in conjunction with state and ferrimanganic in conjunction with state, this two classes form heavy metal elementEasily be subject to the impact of Soil Micro-environment condition, in soil, discharge above-mentioned three class form heavy metals; Be finally residual form, this type of is heavyMetal form does not substantially produce environmental risk effect in soil environment. Visible, heavy metal pollution of soil is administered core for eliminatingWater-soluble state, exchange state and combination state heavy metal environmental risk in soil.

Farmland, Heavy Metal Pollution In Cultivated Land administer content that second aspect should pay close attention to be the soil texture, organic matter, pH,The envirment factor such as oxidation-reduction potential and living things system. Heavy metal element exchanges in Soil Micro-environment system, absorption, networkThe dynamic system effect that close, sedimentation etc. connects each other, mutually restricts, these dynamic system effects directly or indirectly affect heavy metalThere is form in element, and then affect pollution control effect in soil, particularly adopts dosing method to process a compound huge sum of moneyBelong to and polluting, may be owing to cannot reach the envirment factor condition that reduces various heavy environmental risk simultaneously, and cannot reachRegulation effect.

Farmland, the Heavy Metal Pollution In Cultivated Land improvement third aspect should be paid close attention to the ecological functions of soil. The ecology of soilFunctionally all to reach certain condition as soil texture, pH, organic matter, oxidation-reduction potential etc., effectively biological supportGrowth. Soil ecology Functional Requirement should avoid adding less or not adding excessive or too drastic chemicals in soil remediation process as far as possibleMatter, do not change the measures such as soil texture as far as possible, to maintain or to improve soil ecology function.

Heavy-metal contaminated soil is administered and is mainly comprised three classes improvement strategies at present: passivation, dilution and purification. Soil passivation is controlledReason strategy is mainly to reduce heavy metal activity by adding heavy metal stabilization medicament to soil, reduces heavy metal ring thereby reachThe object of border risk. Soil passivation strategy is administered after technical finesse, because pollution factor is still in Soil Micro-environment, and heavy metalThere is the further environmental risk of activation in pollution factor; On the other hand, owing to having added chemical agent in soil, may be to soilEarth physicochemical property, ecological functions exert an influence. It is mainly to reduce heavy metal in soil pollution concentration that strategy is administered in soil dilution,Reach the object that reduces heavy metal environmental risk, the slight pollution that this strategy is only applicable to more than the 30cm of top layer is administered, forThere is not competitive meaning in the above soil remediation of medium pollution level. Soil sanitation administer strategy be extract heavy metal in soil because ofSon, reaches the object that reduces heavy metal-polluted soil total amount, and this tactful improvement technology (as plant extract) is to eliminate heavy metal in soilPollution factor is final purpose. Above-mentioned showing, heavy metal pollution of soil is administered and adopted purification treatment strategy is best, the most thoroughlyAdminister strategy.

Administer existing problems and heavy metal-polluted soil improvement optimal strategy for above-mentioned Present Situation of Soil Heavy Metal Pollution, heavy metalDiscussion, current universally recognized improvement technology is that the biological extractive technique in strategy is administered in soil sanitation, i.e. the super enrichment of plantationPlant carries out extraction and cleaning, then removes the super enriching plant after enriching heavy metal. Biological extractive technique does not produce and disturbs soilMove, effectively kept the Biofunctional of soil, but biological extractive technique has cycle length, is subject to habitat conditions to affect large officeLimit. In addition, super enriching plant conventionally only can be for certain heavy metal species, is mainly used in slight, single heavy metal pollution region and repaiiesMultiple, be difficult to reach desirable repairing effect for compound and medium above pollution level Heavy Metal Pollution Control.

Heavy metal chelating agent is chemical industry medicament a kind of and the powerful chelating of heavy metal ion, can be at normal temperature and very wide pH valueIn condition and range, with the Cu in water body2+、Cd2+、Hg2+、Pb2+、Mn2+、Ni2+、Zn2+、Cr3+Carry out etc. various heavy metal ionChemical reaction, and generate rapidly at short notice the flocculent deposit that insoluble, easy filtration is removed, reach and from water, remove a huge sum of moneyBelong to the object of ion. Heavy metal chelating agent is of a great variety, divides and has powder state, solid state and liquid state by form; Divide and have by compositionInorganic trapping agent and organic trapping agent; Divide by Trapping ways have adsorbing and trapping agent, ion-exchange trapping agent, complexing trapping agent; PressInstitute can trap heavy metals classification can be divided into broad-spectrum heavy metal trapping agent, single type heavy metal chelating agent etc. Heavy metal chelating agentProcess Heavy Metals in Waters and be used widely at water treatment field, have can process compound heavy metal pollution, speed fast,The feature such as the high and cost of efficiency is low. In addition, adopt solid state heavy metal chelating agent to process high concentration, combined pollution electroplating wastewater skillArt studies have reported that, and this heavy metals trapping technology has been processed the Compound Heavy Metals in complicated electroplating wastewater matrix effectively, andDo not dissolve in electroplating wastewater, the compound Heavy Metal Pollution Control of this soil to complex matrices system has huge inspiration meaningJustice. Keep the functional feature of soil ecology for soil matrix complexity, compound heavy metal pollution and need, select applicable weightMetal traps, adopts suitable methods, and it is a kind of that heavy metals trapping technology is introduced into heavy metal pollution of soil improvementPotential strategy.

Summary of the invention

For problems of the prior art, the present invention is proposed.

The present invention proposes a kind of heavy metal pollution of soil original position trapping improvement method. This method comprises:

1) heavy metal chelating agent is packaged in to porous device, water permeable device reaches heavy metal chelating agent and soil isolation, but nativeEarth solution can be in the object without in free access to plant under pressure condition.

2) porous device is embedded in moisture contaminated soil, reaches heavy metal chelating agent complete wetting in containing contaminated soilThe aqueous solution in object.

3) determine that as required porous device is embedded in the time in moisture contaminated soil. When device is embedded in soil water solution,In soil water solution, heavy metal ion is by concentration diffusion and heavy metal chelating agent generation ion-exchange, complexing, absorption etc.React and be captured; Meanwhile, other form heavy metals in soil dynamic equilibrium system, because of the reduction of solubilised state heavy metal concentration,And transform to solubilised state, be finally captured;

4) take out the porous device being embedded in soil, the trapping agent in apparatus for removing after trap heavy metals, thus eliminate soilHeavy metal element in earth.

The present invention's water permeable device used: device mainly comprises Intranet cylindrical shell, intermediate coat net, outer net cylindrical shell and the large portion of side cover fourPoint, heavy metal chelating agent is placed in Intranet cylindrical shell, and two side covers are by screw thread and the fastening of Intranet cylindrical shell, and intermediate coat net adopts outer net cylinderBody and Intranet cylindrical shell clamp.

The present invention selects insoluble heavy metal chelating agent, includes but not limited to various dithiocarbamate salt heavy metalsChelating agent and derivative thereof, xanthate class heavy metal chelant and derivative thereof, heavy metal ion exchanger resin, heavy metal are inhaledAttached resin and other all kinds heavy metal chelate resins etc.

Trapping agent of the present invention filling rate in device is 50% ~ 80%.

Described in the inventive method, heavy metal element comprises: copper, lead, zinc, cadmium, nickel, mercury, arsenic, antimony, chromium, manganese, gold, silver,Thallium, uranium etc.

The present invention can trap heavy metals concentration range: 0.001mg/L ~ 100mg/L.

Trapping agent of the present invention reacts with heavy metal element and can realize by following general formula:

bMa++A→P↓+aNb+

M represents heavy metal element, and A represents heavy metal chelating agent, and P is the rear sedimentation products of trapping, and N represents exchange ion, a and b tableShow chemical valence.

Soil moisture content of the present invention is not less than 85%.

Device of the present invention is embedded in time range in soil at 1 day ~ 360 days, depending on heavy metal pollution of soil degree.

This method major advantage:

1) adopt water permeable device, without pressure can effective water and soil separation, trapping agent separates with soil;

2) select insoluble heavy metal chelating agent, adopt isolation method directly to extract heavy metal in soil water solution, not to soil, there is not soil disturbance and secondary environmental risk factor in middle release chemical substance;

3) can process compound heavy metal pollution;

4) processing rear heavy metal chelating agent can reactivate use or carry out other modes and process disposal;

5) be subject to environmental influence little, operate simple and easy, processing speed is fast, effective, financial cost is cheap.

Detailed description of the invention

Embodiment 1:

Under normal temperature, get the granular insoluble starch xanthates of 50g and be placed in 0.5L device, it is neutral containing that device is immersed in to pHIn the laboratory configuration solution of copper, lead, zinc, cadmium and mercury, leave standstill 30min, take out and measure, heavy metals trapping result is as following table:

Table 1 laboratory configuration solution heavy metals trapping result (unit: mg/L):

The present embodiment result shows, adopt this installation method can remove fast and efficiently in water body compound heavy metal pollution because ofSon, and the further activation processing of heavy metals trapping product that removes out.

Embodiment 2:

Under normal temperature, get 50g xanthate cotton and be placed in 0.5L device, device is placed in to 5L beaker central authorities; Separately get 4kg and cross 100 ordersScreen cloth is leaded, the agricultural land soil sample of zinc and cadmium is placed in beaker, and device is buried; In soil, slowly add distilled water, extremelyNo longer emit bubble, completely submergence soil and device; Leave standstill 48h, take out and measure, heavy metals trapping result is as following table:

Table 2 farmland soil heavy metals trapping result (unit: mg/kg):

In the present embodiment, soil is medium above pollution level sample, and in pedotheque, heavy metal element is through 48h trapping processingAfter, clearance reaches 67.29% ~ 82.65%, has effectively extracted heavy metal in soil pollution factor. It should be noted that in soil heavyMetal relict state content all has reduction in various degree, and this shows that selected heavy metal chelating agent is to heavy metal ion in the soil liquidTrapping, effectively promoted the release in conjunction with state heavy metal element in conjunction with state or ferrimanganic of carbonate in Soil Micro-environment.

Embodiment 3:

Under normal temperature, get 50g bagasse cellulose xanthate and be placed in 0.5L device, device is placed in to 5L beaker central authorities; Separately get 4kgThe urban soil sample of crossing 100 eye mesh screen cuprics, lead, zinc and cadmium is placed in beaker, and device is buried; In soil, slowly addDistilled water, to no longer emitting bubble, submergence soil and device completely; Leave standstill 24h, take out and measure, heavy metals trapping result is as following table:

Table 3 farmland soil heavy metals trapping result (unit: mg/kg):

In the present embodiment, soil is slight pollution sample, in pedotheque heavy metal element after 24h trapping is processed, clearanceBetween 22.27% ~ 37.20%, there is remarkable treatment effect. The present embodiment is lower with respect to previous example farmland sample clearance,May be because this pedotheque relict state content of beary metal is higher or trapping deficiency of time.

The object that finally it should be noted that the mode of publicizing and implementing is to help further to understand the present invention, but abilityThe technical staff in territory is understood that without departing from the spirit and scope of the invention and the appended claims, various replacements andAmendment is all possible. Therefore, the present invention should not be limited to the disclosed content of embodiment, the scope of protection of present invention withThe scope that claims define is as the criterion.

Claims (10)

1. a heavy metal pollution of soil original position trapping improvement method, is characterized in that comprising the steps:
(1) heavy metal chelating agent is packaged in to porous device, water permeable device reaches heavy metal chelating agent and soil isolation, but nativeEarth solution can be in the object without in free access to plant under pressure condition;
(2) porous device is embedded in moisture contaminated soil, reaches heavy metal chelating agent complete wetting in containing contaminated soilObject in the aqueous solution;
(3) determine that as required porous device is embedded in the time in moisture contaminated soil, when device is embedded in soil water solution, soilIn the aqueous solution, heavy metal ion is reacted with heavy metal chelating agent generation ion-exchange, complexing, absorption etc. by concentration diffusionAnd be captured; Meanwhile, other form heavy metals in soil dynamic equilibrium system, because of the reduction of solubilised state heavy metal concentration, and toSolubilised state transforms, and is finally captured;
(4) take out the porous device being embedded in soil, the trapping agent in apparatus for removing after trap heavy metals, thus eliminate soilHeavy metal element in earth.
2. heavy metal pollution of soil original position trapping improvement method as claimed in claim 1, is characterized in that adopting water permeable deviceEncapsulation heavy metal chelating agent, water permeable device can effectively be isolated heavy metal chelating agent and soil, but the soil liquid can be without pressureUnder condition, in free access to plant, contact with heavy metal chelating agent.
3. heavy metal pollution of soil original position as claimed in claim 1 trapping improvement method, it is characterized in that water permeable device by outsideNet cylindrical shell, intermediate coat net, Intranet cylindrical shell three parts compositions, outer screen distance 10mm ~ 20mm, mesh evenly tiles, outside coverage rate isNet drum surface long-pending 100%; Intermediate coat screen distance 0.01mm ~ 1mm, mesh evenly tiles, coverage rate 100%; Interior screen distance 3mm~ 6mm, mesh evenly tiles, coverage rate be Intranet drum surface long-pending 60% ~ 80%, outer net cylindrical shell and Intranet cylindrical shell all have and prop upSupport effect, intermediate coat net optionally adopts glued membrane, fiber, metal or plastic material.
4. heavy metal pollution of soil original position as claimed in claim 1 trapping improvement method, is characterized in that described heavy metal catchesCollection agent be insoluble trapping agent, include but not limited to various dithiocarbamate salt heavy metal chelants and derivative thereof,Xanthate class heavy metal chelant and derivative thereof, heavy metal ion exchanger resin, heavy metal adsorption resin and other are variousType heavy metal chelate resin etc.
5. heavy metal pollution of soil original position as claimed in claim 1 trapping improvement method, is characterized in that described heavy metal catchesCollection agent filling rate in device is 50% ~ 80%.
6. heavy metal pollution of soil original position as claimed in claim 1 trapping improvement method, is characterized in that described heavy metal unitElement comprises: copper, lead, zinc, cadmium, nickel, mercury, arsenic, antimony, chromium, manganese, gold, silver, thallium, uranium etc.
7. heavy metal pollution of soil original position trapping improvement method as claimed in claim 1, is characterized in that described water permeable deviceBe embedded in moisture contaminated soil time range at 1 day ~ 360 days.
8. heavy metal pollution of soil original position trapping improvement method as claimed in claim 1, is characterized in that described soil is water-solubleThe heavy metal concentration scope that can trap in liquid is at 0.001mg/L ~ 100mg/L.
9. heavy metal pollution of soil original position trapping improvement method as claimed in claim 1, is characterized in that described embedding permeableThe moisture content of the moisture contaminated soil of device is not less than 85%.
10. heavy metal pollution of soil original position trapping improvement method as claimed in claim 1, is characterized in that described method except answeringFor administering containing heavy-metal contaminated soil water aqueous solution original position, can also be applied to sludge containing heavy metal, contain heavy metal bed mud, containHeavy metal water body in-situ is administered.
CN201510742189.6A 2015-11-05 2015-11-05 Soil heavy metal pollution in-suit capturing treating method CN105598152A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105945062A (en) * 2016-06-12 2016-09-21 上海大学 Method for chelating heavy metal in contaminated soil through temperature-sensitive polymer

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101021515A (en) * 2007-03-09 2007-08-22 东北大学 Method for in-situ sampling, separating enriching and measuring heavy metal ion in water body
CN102320686A (en) * 2011-06-27 2012-01-18 吴正建 Device and method for rapidly purifying, repairing and filtering heavy metal polluted water and soil
CN102491603A (en) * 2011-12-29 2012-06-13 北京市环境保护科学研究院 Air injection system and method for in situ restoration of volatile pollutant in underground water
CN103736719A (en) * 2014-01-02 2014-04-23 重庆绿色智能技术研究院 In-situ self-sustaining contaminated soil restoring device based on plant bionics and method

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101021515A (en) * 2007-03-09 2007-08-22 东北大学 Method for in-situ sampling, separating enriching and measuring heavy metal ion in water body
CN102320686A (en) * 2011-06-27 2012-01-18 吴正建 Device and method for rapidly purifying, repairing and filtering heavy metal polluted water and soil
CN102491603A (en) * 2011-12-29 2012-06-13 北京市环境保护科学研究院 Air injection system and method for in situ restoration of volatile pollutant in underground water
CN103736719A (en) * 2014-01-02 2014-04-23 重庆绿色智能技术研究院 In-situ self-sustaining contaminated soil restoring device based on plant bionics and method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105945062A (en) * 2016-06-12 2016-09-21 上海大学 Method for chelating heavy metal in contaminated soil through temperature-sensitive polymer

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