CN104874601A - Competitive-adsorption-based in-situ quick restoration method for cadmium-polluted paddy field - Google Patents

Competitive-adsorption-based in-situ quick restoration method for cadmium-polluted paddy field Download PDF

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Publication number
CN104874601A
CN104874601A CN201510304018.5A CN201510304018A CN104874601A CN 104874601 A CN104874601 A CN 104874601A CN 201510304018 A CN201510304018 A CN 201510304018A CN 104874601 A CN104874601 A CN 104874601A
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China
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cadmium
soil
paddy
complexing agent
weaving cloth
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CN201510304018.5A
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Chinese (zh)
Inventor
魏俊富
崔莉
孔志云
王会才
赵孔银
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天津工业大学
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Priority to CN201510304018.5A priority Critical patent/CN104874601A/en
Publication of CN104874601A publication Critical patent/CN104874601A/en

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Abstract

The invention relates to an in-situ quick restoration method for a cadmium-polluted paddy field. A complexing agent aqueous solution is sprayed into water in the cadmium-polluted paddy field; the rotary-tillage mixing is carried out; cadmium ions are dissolved out in the water in the paddy field in an in-situ complexing manner from polluted soil; chelate functional non-woven fabric with a stronger chelation action is quickly put into the paddy field and is constantly moved so that the chelate functional non-woven fabric is enabled to carry out competitive adsorption sufficiently; heavy-metal cadmium is transferred onto the non-woven fabric from a liquid-phase aqueous solution; afterwards, the non-woven fabric is taken out; a complexing agent is released and regenerated at the same time. The complexing agent which is environment-friendly and high-efficiency and is further economical and practical is selected and used for the in-situ quick restoration method for the cadmium-polluted paddy field, and cannot cause secondary pollution after being used. By using the in-situ quick restoration method for the cadmium-polluted paddy field, the heavy-metal cadmium in soil can be thoroughly removed, and the in-situ quick restoration method for the cadmium-polluted paddy field has the characteristics of simpleness in operation, low cost, high restoration effect, short restoration period and the like when being applied to the cadmium-polluted paddy field. The paddy field which is treated for one day by applying a technique provided by the invention can be carried out with agricultural planting. The invention provides an energy-saving, quick and environment-friendly in-situ restoration method for the soil in the paddy field which is polluted by the heavy-metal cadmium.

Description

A kind of in-situ rapid renovation method of the cadmium pollution rice field based on competitive Adsorption

Technical field

The present invention relates to a kind of in-situ rapid renovation cadmium pollution, and utilize the principle of competitive Adsorption thoroughly to remove the heavy metal cadmium in soil and complexing agent realized to the method for cycling and reutilization, belong to heavy-metal contaminated soil based technique for in-situ remediation field in environmental protection.

Background technology

In recent years, along with Chinese fast industrialization and urbanization, plurality of heavy metal is discharged by all means in environment, adds the heavy metal burden of environment, causes serious heavy metal pollution of soil problem." national Soil Pollution Investigation publication " shows, China's By The Heavy Metal Contaminated Soil outstanding problem, and exceeding standard rate is 13.3%, and middle serious pollution is ploughed and reached about 5,000 ten thousand mu, and presents increasing trend.In all multi-metals of contaminated environment, cadmium pollution is the most serious, and it is reported, the cadmium be discharged in environment has 82% ~ 94% to enter soil.Cadmium content generally increases in China, not only causes quality and the Quality Down of agricultural product, and serious threat health, and therefore, the improvement of heavy metal cadmium and reparation have become the Vital Strategic Problems that China is badly in need of solving at present.Showering is focused on contaminated soil transfer, and because such methods engineering amount is large, processing cost is high, is not suitable for the reparation of large area heavy-metal contaminated soil.In-situ immobilization, because of the superiority on its operation and cost, is primary selection facing in Heavy Metal Pollution Control.Electro reclamation method studies more a kind of original position soil restorative procedure, and this method is simple to operate, treatment effeciency is high, but be only applicable to small size pollution, and execute-in-place difficulty is large.At present, the report of concerns about bio method is also more, the method is easy to implement, and invests less, environmental friendliness, but adopt phytoremediation required time longer, for sudden heavy metal pollution of soil, high density pollution level is unfavorable for plant growth, and therefore effect is undesirable, also need the screening considering bacterial strain, environment is to the variation effect etc. of microorganism.In-situ chemical soil ablution adds cleaning material in contaminated soil, leaches the recovery technique of removing heavy metal with liquid state mixing, owing to being the method for chemistry, so it is high to have removing efficiency, and the advantage that can repair in a short time.But using such medicament aqueous solution, water cleans in the method for soil, produce a large amount of waste liquids containing heavy metal, in order to process it, need drain treatment apparatus, dewater unit.Have when this device is set that cost is extremely many, cost uprises such problem.In addition, the situation that the equipment such as drain treatment apparatus cannot be set because of the place of purification object soil can also be there is.

Notification number is the Chinese invention patent of CN103143557, disclose " a kind of plumbous cadmium composite modifying agent for paddy soil and methods for making and using same thereof ", this invention with calcium carbonate, hydroxyapatite, sepiolite, zeolite for raw material, prepare a kind of plumbous cadmium composite modifying agent, use the modifying agent of various dose according to different pollution level.This invention belongs to traditional fixation in situ one passivating technique, only reduce bioavailability of heavy metals, but heavy metal still resides in soil, there is the deficiency of secondary pollution risk.

Notification number is the Chinese invention patent of CN103894407A, disclose " a kind of method of restoration of soil polluted by heavy metal ", this invention is adsorbed by adding lightweight modified mineral clay absorbent, the adsorbent completing absorption of keeping afloat is pulled out after absorption, but, this adsorbent only has good adsorption effect to the heavy metal ion in the topsoil aqueous solution, is difficult to remove for the compact heavy metal ion of soil particle.

Notification number is the Chinese invention patent of CN103143561A, disclose " a kind of method that low cost removes heavy metal pollution of soil ", this invention by applying heavy metal scavenger in paddy field water, promote the dissolving wash-out of heavy metal in soil, heavy metal is from soil particle surface desorption/dissolving, be discharged in water, the water containing heavy metal is concentrated to be discharged into storage area, completes the improvement of middle and high concentration heavy-metal contaminated soil in the short time.But the method is difficult to disposablely to be removed completely by heavy metal in soil, cause workload large and need process a large amount of heavy metal wastewater therebies, the heavy metal pollution closing on rice field also can be caused in storage area.

Summary of the invention

The present invention is directed to existing cadmium pollution serious, difficult treatment, recovery project amount is large, rehabilitation cost is high and there is the problem of follow-up risk etc., in proposition cadmium pollution rice field, heavy metal cadmium ion is from contaminated soil situ complexing stripping to paddy field water, chelating function non-weaving cloth competitive Adsorption from water is removed, the in-situ rapid renovation new method of complexing agent regeneration release cycle application, and its concrete technical scheme is as follows:

Based on the in-situ rapid renovation method in the cadmium pollution rice field of competitive Adsorption, comprise the steps:

A) in cadmium pollution paddy field water, spray the complexing agent aqueous solution of 0.01 ~ 2mol/L, the amount of adding complexing agent is 1 ~ 1000 quality times of Cadmium in Soil content, it is 10 ~ 45cm that interpolation complexing agent aqueous solution or water make to plough the degree of depth of coiling the water surface, make the heavy metal cadmium complexing in complexing agent and soil, cadmium is transferred to liquid phase water solution from solid phase soil;

B) use the tractor being provided with rotary cultivator by soil and aqueous solution rotary tillage mixing, make the abundant stripping of the heavy metal cadmium in soil, rotary tillage mixing time is 1 ~ 30min;

C) in rice field, drop into rapidly chelating function non-weaving cloth offset is dynamic and its sufficient competition adsorb, adsorption time is 1 ~ 10min, and the quality of the chelating function non-weaving cloth of each input is 1 ~ 10g/m 2, heavy metal cadmium moves on to non-weaving cloth from liquid phase Transfer in Aqueous Solution, is taken out by non-weaving cloth afterwards;

D) heavy metal cadmium be combined with complexing agent in liquid phase water solution is had the chelating function non-weaving cloth competitive Adsorption of stronger chelation, and complexing agent obtains release regeneration simultaneously;

E) circulate next time, namely repeat step b)-d), until Cadmium in Soil content reaches standard of soil environment quality;

F) become soil and supernatant water solution by standing separation, the supernatant water solution containing complexing agent can be used for repairing other cadmium pollution rice fields.

The present invention's complexing agent used, humic acid, citric acid, tartaric acid, malic acid, oxalic acid, acetic acid, poly-aspartate etc. can be enumerated, contained by different contaminated soil, heavy metal contamination is different, certain adjustment can be carried out to parameters such as the kind of complexing agent, concentration, processing time, drip washing number of times, Cadmium in Soil ion can be quickly transferred in upper water by complexing agent used, and environmental friendliness.Select environmental protection, efficient and economical and practical complexing agent, after using, can not secondary pollution be caused.Complexing agent can recycled for multiple times, greatly reduces processing cost, alleviates environmental pressure, have important environment and economy meaning.

The present invention's non-weaving cloth used is the chelating non-weaving cloth of one or more groups had in amino, carboxyl, hydroxyl, amide groups, amide groups, ghiourea group, quaternary ammonium group, amidoxime group, sulfydryl, aminooimidazole, thioamides, thiosemicarbazides, amino sulfanilamide (SN), sulphonylimidazole, this non-weaving cloth can by complex status cadmium quick adsorption in paddy field water, and saturated extent of adsorption can reach 5 ~ 100mg/g.

Heavy metal cadmium in soil can thoroughly be removed by the present invention, be applied to cadmium pollution rice field and there is simple to operate, the feature such as cost is low, repairing effect is high, repairing efficiency is short, applied widely, non-secondary pollution, simplify soil remediation program, reduce soil remediation cost, improve soil quality.Agricultural planting can be carried out in the application rice field of the technology of the present invention process after one day, and the present invention is that the paddy soil of polluted by heavy metal cadmium provides a kind of energy-conservation, quick, eco-friendly in-situ remediation method.

Detailed description of the invention:

Embodiment 1:

At cadmium pollution rice field (in soil, total cadmium content is 3.1mg/kg) the middle citric acid solution applying 0.01mol/L, making to plough the degree of depth of coiling the water surface is 10cm, and the amount of adding complexing agent is 1000 quality times of Cadmium in Soil content; Use the tractor being provided with rotary cultivator that soil and aqueous solution rotary tillage are stirred 2min, make the heavy metal solution-off in soil; 10g/m is pressed rapidly in rice field 2drop into have hydroxyl, carboxyl chelating function non-weaving cloth not offset move after 3min makes it fully adsorb, non-weaving cloth is taken out; Circulate, after 4 circulations, Cadmium in Soil content is 0.21mg/kg, reaches standard of soil environment quality, completes soil remediation next time.

Embodiment 2:

At cadmium pollution rice field (in soil, total cadmium content is 1.4mg/kg) the middle tartaric acid solution applying 0.05mol/L, making to plough the degree of depth of coiling the water surface is 30cm, and the amount of adding complexing agent is 800 quality times of Cadmium in Soil content; Use the tractor being provided with rotary cultivator that soil and aqueous solution rotary tillage are stirred 10min, make the heavy metal solution-off in soil; 8g/m is pressed rapidly in rice field 2drop into have amino, amide groups chelating function non-weaving cloth not offset move after 5min makes it fully adsorb, non-weaving cloth is taken out; Circulate, after 3 circulations, Cadmium in Soil content is 0.25mg/kg, reaches standard of soil environment quality, completes soil remediation next time.

Embodiment 3:

At cadmium pollution rice field (in soil, total cadmium content is 0.8mg/kg) the middle malic acid solution applying 0.10mol/L, making to plough the degree of depth of coiling the water surface is 25cm, and the amount of adding complexing agent is 500 quality times of Cadmium in Soil content; Use the tractor being provided with rotary cultivator that soil and aqueous solution rotary tillage are stirred 30min, make the heavy metal solution-off in soil; 5g/m is pressed rapidly in rice field 2drop into there is ghiourea group chelating function non-weaving cloth not offset move after 2min makes it fully adsorb, non-weaving cloth is taken out; Circulate, after 2 circulations, Cadmium in Soil content is 0.22mg/kg, reaches standard of soil environment quality, completes soil remediation next time.

Embodiment 4:

At cadmium pollution rice field (in soil, total cadmium content is 0.5mg/kg) the middle oxalic acid solution applying 1.0mol/L, making to plough the degree of depth of coiling the water surface is 45cm, and the amount of adding complexing agent is 900 quality times of Cadmium in Soil content; Use the tractor being provided with rotary cultivator that soil and aqueous solution rotary tillage are stirred 5min, make the heavy metal solution-off in soil; 2g/m is pressed rapidly in rice field 2drop into have amidoxime group, sulfydryl chelating function non-weaving cloth not offset move after 10min makes it fully adsorb, non-weaving cloth is taken out; Circulate, after 1 circulation, Cadmium in Soil content is 0.27mg/kg, reaches standard of soil environment quality, completes soil remediation next time.

Above-described embodiment is the present invention's preferably implementation, and in addition, the present invention can also realize by alternate manner, and any apparent replacement is all within protection scope of the present invention without departing from the inventive concept of the premise.

Claims (8)

1. the in-situ rapid renovation method based on the cadmium pollution rice field of competitive Adsorption, described method is that a kind of cadmium ion is from contaminated soil situ complexing stripping to paddy field water, chelating function non-weaving cloth competitive Adsorption from water is removed, the in-situ rapid renovation new method of complexing agent regeneration release cycle application, it is characterized in that, comprise the steps:
A) in cadmium pollution paddy field water, spray the heavy metal cadmium complexing that complexing agent aqueous solution makes in itself and soil, cadmium is transferred in liquid phase water solution from solid phase soil;
B) use the tractor being provided with rotary cultivator by soil and aqueous solution rotary tillage mixing, make the abundant stripping of the heavy metal cadmium in soil;
C) in rice field, drop into rapidly chelating function non-weaving cloth offset is dynamic and its sufficient competition is adsorbed, heavy metal cadmium moves on to non-weaving cloth from liquid phase Transfer in Aqueous Solution, is taken out by non-weaving cloth afterwards;
D) heavy metal cadmium be combined with complexing agent in liquid phase water solution is had the chelating function non-weaving cloth competitive Adsorption of stronger chelation, and complexing agent obtains release regeneration simultaneously;
E) circulate next time, namely repeat step b)-d), until Cadmium in Soil content reaches standard of soil environment quality;
F) become soil and supernatant water solution by standing separation, the supernatant water solution containing complexing agent can be used for repairing other cadmium pollution rice fields.
2. the in-situ rapid renovation method in a kind of cadmium pollution rice field based on competitive Adsorption according to claim 1, it is characterized in that interpolation complexing agent aqueous solution or water make to plough the degree of depth of coiling the water surface is 10 ~ 45cm, and the amount of adding complexing agent is 1 ~ 1000 quality times of Cadmium in Soil content.
3. the in-situ rapid renovation method in a kind of cadmium pollution rice field based on competitive Adsorption according to claim 1, it is characterized in that with the organic acid of 0.01 ~ 2mol/L for complexing agent, comprise humic acid, citric acid, tartaric acid, malic acid, oxalic acid, acetic acid, poly-aspartate, Cadmium in Soil ion can be quickly transferred in upper water solution by complexing agent used, and environmental friendliness.
4. the in-situ rapid renovation method in a kind of cadmium pollution rice field based on competitive Adsorption according to claim 1, after it is characterized in that adding complexing agent, rotary tillage mixing time is 1 ~ 30min.
5. the in-situ rapid renovation method in a kind of cadmium pollution rice field based on competitive Adsorption according to claim 1, it is characterized in that non-weaving cloth used is the chelating non-weaving cloth of one or more groups had in amino, carboxyl, hydroxyl, amide groups, sulfydryl, amidoxime group, ghiourea group, this non-weaving cloth can by complex status cadmium quick adsorption in paddy field water, and saturated extent of adsorption can reach 5 ~ 100mg/g.
6. the in-situ rapid renovation method in a kind of cadmium pollution rice field based on competitive Adsorption according to claim 1, it is characterized in that earth not completely sedimentation time this non-weaving cloth can be used to carry out quick adsorption, adsorption time is 1 ~ 10min, and the quality of each chelating function non-weaving cloth dropped into is 1 ~ 10g/m 2, same non-weaving cloth can repeatedly use until adsorb saturated.
7. the in-situ rapid renovation method in a kind of cadmium pollution rice field based on competitive Adsorption according to claim 1, after it is characterized in that non-weaving cloth adsorbing heavy metal cadmium, complexing agent is renewable to be recycled.
8. the in-situ rapid renovation method in a kind of cadmium pollution rice field based on competitive Adsorption according to claim 1, is characterized in that contaminated soil can be passed through repeatedly circulation complexing stripping-chelating function non-weaving cloth competitive Adsorption, completes soil remediation.
CN201510304018.5A 2015-06-03 2015-06-03 Competitive-adsorption-based in-situ quick restoration method for cadmium-polluted paddy field CN104874601A (en)

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Publication number Priority date Publication date Assignee Title
CN105689371A (en) * 2015-12-13 2016-06-22 深圳多元拓展环保科技有限公司 In-situ capturing treatment method for soil heavy metal pollution
CN107737803A (en) * 2017-11-24 2018-02-27 湖南新九方科技有限公司 A kind of restorative procedure in heavy metal cadmium arable land
CN108480379A (en) * 2018-03-19 2018-09-04 湖北娅安科技开发有限公司 A kind of mercury or other heavy-metal contaminated soil renovation agents and preparation method thereof
CN108889773A (en) * 2018-05-29 2018-11-27 深圳文科园林股份有限公司 A kind of cadmium pollution mine soil renovation agent and preparation and application method
CN110014032A (en) * 2019-04-28 2019-07-16 北京建工环境修复股份有限公司 A kind of restorative procedure of farmland soil heavy metals pollution

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105689371A (en) * 2015-12-13 2016-06-22 深圳多元拓展环保科技有限公司 In-situ capturing treatment method for soil heavy metal pollution
CN105689371B (en) * 2015-12-13 2019-06-07 深圳多元拓展环保科技有限公司 A kind of heavy metal pollution of soil original position trapping administering method
CN107737803A (en) * 2017-11-24 2018-02-27 湖南新九方科技有限公司 A kind of restorative procedure in heavy metal cadmium arable land
CN108480379A (en) * 2018-03-19 2018-09-04 湖北娅安科技开发有限公司 A kind of mercury or other heavy-metal contaminated soil renovation agents and preparation method thereof
CN108889773A (en) * 2018-05-29 2018-11-27 深圳文科园林股份有限公司 A kind of cadmium pollution mine soil renovation agent and preparation and application method
CN110014032A (en) * 2019-04-28 2019-07-16 北京建工环境修复股份有限公司 A kind of restorative procedure of farmland soil heavy metals pollution

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