CN101962554A - Montmorillonite-containing curing agent used for treating heavy metal contaminated soil - Google Patents

Montmorillonite-containing curing agent used for treating heavy metal contaminated soil Download PDF

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Publication number
CN101962554A
CN101962554A CN2010102884808A CN201010288480A CN101962554A CN 101962554 A CN101962554 A CN 101962554A CN 2010102884808 A CN2010102884808 A CN 2010102884808A CN 201010288480 A CN201010288480 A CN 201010288480A CN 101962554 A CN101962554 A CN 101962554A
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China
Prior art keywords
solidifying agent
soil
heavy metal
contaminated soil
montmorillonite
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Pending
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CN2010102884808A
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Chinese (zh)
Inventor
席永慧
吴晓峰
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Tongji University
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Tongji University
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Priority to CN2010102884808A priority Critical patent/CN101962554A/en
Publication of CN101962554A publication Critical patent/CN101962554A/en
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Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00017—Aspects relating to the protection of the environment
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00758—Uses not provided for elsewhere in C04B2111/00 for agri-, sylvi- or piscicultural or cattle-breeding applications
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00767—Uses not provided for elsewhere in C04B2111/00 for waste stabilisation purposes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00—Technologies for solid waste management
    • Y02W30/50—Reuse, recycling or recovery technologies
    • Y02W30/91—Use of waste materials as fillers for mortars or concrete

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Processing Of Solid Wastes (AREA)

Abstract

The invention relates to the technical field of contaminated soil treatment, in particular to a montmorillonite-containing curing agent used for treating heavy metal contaminated soil. The curing agent comprises the following components in percentage by weight: 25 to 40 percent of cement, 40 to 60 percent of montmorillonite and 10 to 20 percent of quick lime. The curing agent has the advantages that: the montmorillonite fixes heavy metal ions, simultaneously has no risk of secondary contamination and cannot change the properties of original soil remarkably. The mineral components of the montmorillonite are very close to those of undisturbed silty clay, which avoids great damage to a soil structure caused by the cement and the quick lime. Due to the advantage, the curing agent has a particularly remarkable repair effect on a heavy metal non-point source contaminated agricultural land, and has good social, economic and environmental benefits.

Description

Be used to administer the montmorillonoid-containing solidifying agent of heavy-metal contaminated soil
Technical field
The present invention relates to contaminated soil and administer technical field, particularly a kind of montmorillonoid-containing solidifying agent that is used to administer heavy-metal contaminated soil.
Background technology
At present, the recovery technique of heavy-metal contaminated soil mainly contains: cushion, biological restoration method, chemical fixation, electronic repairing method etc.Wherein, cushion only is applicable to small area, serious pollution soil; The biological restoration method have processing costs low, can reach higher cleaning water equality advantage, but required repair time is long, contaminated thing class limitations is bigger; Electronic repairing method effect in different soil property soil differs, even adverse effect is arranged, and the high operating equipment complexity of cost, is unfavorable for the big area use.It is by adding heavy metal element in different allogenic materials (the being solidifying agent) fixing soil, reaching a kind of important method that reduces heavy metal transport property and biological effectiveness that heavy-metal contaminated soil solidifies recovery technique.Since easy to operate quick with effect, make it that not replaceable effect be arranged in the contaminated soil governance process.Adopt laboratory evaluation, can assess these fixed substances fixed efficiency to heavy metal ion in soil on the one hand; Can assess the ecological risks such as stripping, release and bio-toxicity of heavy metal on the other hand.
At present, main solidifying agent has cement, lime, flyash etc.Its main drawback has: applicable surface is narrower, and promptly some solidifying agent is effectively relatively poor for other then effect for some heavy metal ion; The cost height; Itself there is secondary pollution in some solidifying agent, as flyash; The long-term solidification effect instability of solidifying agent has the danger that discharges again thereby easily decompose the heavy metal ion that is fixed after 1 year as organic solidifying agent.
And adopt above-mentioned solidifying agent to carry out contaminated soil and administer, though the contaminated soil after administering can be used as stopping composition such as ground, roadbed and uses, but the periphery of often administering contaminated soil does not have this type of building operation operation, can not plant vegetation and add on the contaminated soil behind the solidifying agent such as cement, lime, can only be buried go into underground.
Summary of the invention
The objective of the invention is according to above-mentioned the deficiencies in the prior art part, a kind of montmorillonoid-containing solidifying agent that is used to administer heavy-metal contaminated soil is provided, this solidifying agent adopting montmorillonite substitutes the destruction traditional solidifying agent clearly to soil such as part cement, flyash and unslaked lime, thereby the content of these materials in the reduction solidifying agent provides a kind of efficient, economy, heavy-metal contaminated soil solidifying agent that versatility is wide.And can solve the second stage employ problem of cured product.
The object of the invention realizes being finished by following technical scheme:
A kind of montmorillonoid-containing solidifying agent that is used to administer heavy-metal contaminated soil is characterized in that the weight percent of described solidifying agent is: cement 25-40%, polynite 40%-65%, unslaked lime 10%-20%.
The weight percent of described solidifying agent is: cement 30-40%, polynite 40%-60%, unslaked lime 10%-15%.
The weight percent of described solidifying agent is: cement 30%-40%, polynite 50%-55%, unslaked lime 10%-15%.
The using method of described solidifying agent is: described solidifying agent is added directly to heavy-metal contaminated soil and mixing, and adding proportion is the 10%-20% of contaminated soil weight.
Described solidifying agent is used for the improvement of lead pollution of soil.
Advantage of the present invention is: when heavy metal ion is fixed in polynite, do not have the risk of secondary pollution, the character of original soil is not had significant change.The mineral composition of polynite is in close proximity to the original state silty clay, avoided cement and unslaked lime to soil structures cause than havoc.This advantage makes this kind solidifying agent especially remarkable for the farming land repairing effect that is subjected to the heavy metal pollution of area source, has good society, economy, environmental benefit.
Embodiment
By the following examples feature of the present invention and other correlated characteristic are described in further detail, so that technician's of the same trade understanding:
Each components selection thinking of the present invention is: cement as main jointing compound under higher alkaline environment easily and heavy metal ion (as Pb, Gd etc.) form the mixture of indissoluble, thereby stable firmly heavy metal ion; Heavy metal ion in the polynite absorption soil, and can utilize the package action of cement to fix the heavy metal ion that is adsorbed; And unslaked lime is mainly used to provide a higher alkaline environment because under higher alkaline environment fixed effect the best of cured product.
The composition analysis of polynite is as follows:
The sample title Na 2O MgO Al 2O 3 SiO 2 SO 3 K 2O CaO TiO 2 Cr 2O 3 MnO Fe 2O 3 SrO BaO
Silty clay 1.95 1.88 9.32 59.2 0.04 1.96 4.12 0.62 — 0.07 3.29 0.02 —
Polynite 3.68 3.15 13.9 51.2 — 0.77 2.32 0.08 — 0.03 1.2 0.02 —
The mineral composition that can obviously find out polynite from last table is in close proximity to original state silty clay used in the experiment.And in the agricultural application of reality, because the absorption property that polynite had can make clayed soil increase permeability, so can improve the soil.In the soil of plants such as plantation fruit tree, vegetables, flowers and plants, grain, admix polynite and can regulate moisture and air in the soil, protect fertile water conservation, prevent from mould, mashed root and tan by the sun phenomenon such as death to occur, promote that plant grows vigorously.And can be used as the carrier of agricultural chemicals, fertilizer, be processed into long lasting fertilizer or agricultural chemicals and use.
And the main component of cement and lime is calcium oxide, is added into after the soil, and the proterties of soil is constantly alkalized, and the acid base equilibrium of plant is destroyed like this, causes growth and development of plant bad, and severe patient can be dead.
So attempt the common turfgrass of the alkali proof turf establishment industry of plantation in the soil after curing, reduce cement, lime with comparison, after the increase polynite, for the influence of soil.
Because the effect difference that cement, lime and polynite three are played, following three's proportioning experimentizes, and experimentation is as follows:
(1) in the undisturbed soil that is polluted, add heavy metal contaminants, and thorough mixing evenly obtains preparation pollution soil;
(2) interpolation solidifying agent and maintenance obtained cured product in 28 days in polluting soil;
(3) mainly with reference to toxicity leaching program (the being TCLP) standard of U.S. Environmental Protection Administration, utilize deionized water to contrast simultaneously, cured product is carried out leaching experiment with the checking solidification effect as leach liquor;
(4) cured product is packed in the ceramic jar, every altar is adorned 20 in the selected tall grass seed of native 10kg and uniform broadcasting, the back thinning of emerging, and every altar stays 10 strains, and at sowing opening entry plant height after 1 month, every 10 days records once.
Wherein, soil pollutant is a lead ion, and its pollution level is 10000 mg/L; The total volume of solidifying agent is 15%, and both addition was approximately 17.6% of soil weight.Its experimental data is as follows:
Table 1
425 cement Lime Sepiolite TCLP(mg/L) Deionized water leaches (mg/L) Percentage of germination (%) 40 days blade situations
100% - - 0.6 0 0 -
67% 33% - 0 10.35 0 -
33% - 67% 6.83 0 24.6 Be grass green, blade tip is withered and yellow
40% - 60% 5.13 0
25% 10% 65% 4.5 0 13.4 Yellow, part is withered and yellow
30% 8% 62% 3.21 0
30% 10% 60% 2.05 0 11.5 Yellow, part is withered and yellow
30% 12% 58% 2.16 0.5
30% 15% 55% 0.92 1.52 5.5 Yellow, most of withered and yellow
30% 20% 50% 0.35 3.68
30% 25% 45% 0.37 5.26 0 -
34% 12% 54% 0.78 0.54 7.9 Yellow, part is withered and yellow
35% 15% 50% 0 1.05 2.8 Yellow, most of withered
40% 12% 48% 0 0
40% 20% 40% 0 2.83 0.9 Dead
45% 12% 43% 0 0
50% 15% 35% 0 0.56 0 -
By above-mentioned data as can be seen, experimental result each components selection thinking of the present invention of having coincide preferably:
Lime mainly plays and changes soil alkalescence, so under the situation of not adding lime, the solidification effect of solidifying agent is desirable not to the utmost, but too much interpolation can not improve the effect of solidifying agent too.And in the accounting condition with higher, instead influenced the cement of other its solidifications, the accounting of polynite, instead solidification effect descends.Can find out by data, when weight ratio is at 10-15% in solidifying agent, be preferred proportioning at lime.
The solidification effect of cement is better than polynite.So add under the stable situation of proportioning at lime, the ratio solidification effect that improves cement is better, but also improves relatively for soil fail, polynite improves or is reduced in the accounting of solidifying agent, and its change trend is exactly opposite with cement.
Taking all factors into consideration two kinds of trend of lead ion solidification effect and tall grass upgrowth situation, the proportioning of solidifying agent should be cement 25-40%, polynite 40%-65%, unslaked lime 10%-20% substantially; Further select to be: cement 30-40%, polynite 40%-60%, unslaked lime 10%-15%; Concrete preferred proportioning is as follows:
The weight percent of solidifying agent is: cement 30%-40%, polynite 50%-55%, unslaked lime 10%-15%.
More than experiment mainly is to select a kind of proper curing agents proportioning.Whether have good solidification effect equally for testing above selected solidifying agent, below further test according to above-mentioned experimental procedure (remove tall grass plantation step) for other heavy metal ion:
Following experimental result is being that select proportioning: contents of many kinds of heavy metal ion is handled in 33% cement+12% unslaked lime+55% polynite under 15% the level at total volume.
Table 2
Heavy metal ion Pollution level (mg/kg) TCLP?(mg/L) Deionized water leaches (mg/L)
Pb 10000 0.78 0.54
Zn 10000 30.12 0
Gd 1000 0.06 0
As seen from Table 2, polynite has absorption, solidified effect preferably equally for the heavy metal ion of other kinds.The selection thinking of this curing agent component of the present invention that coincide too, polynite is an inert material, mainly is the effect of utilizing its absorption, so its absorption, solidification effect are not limited by the heavy metal ion kind.
In conjunction with above-mentioned experimental result, below under the different situation of the total volume of solidifying agent, select one of them more excellent fixed mixing ratio: the lead ion result is handled in 33% cement+12% unslaked lime+55% polynite.Wherein, pollution level is 10000mg/kg.
Table 3
Total incorporation with respect to soil TCLP?(mg/L) Deionized water leaches (mg/L)
5% 24.04 5.22
10% 7.35 2.48
15% 0.78 0.54
20% 0.07 0
Below as can be seen, be under the 10000mg/kg situation in the lead ion pollution level, the solidifying agent addition is comparatively desirable at 15%-20%.And improve under the relatively low situation addition of then corresponding increase solidifying agent in pollution level.

Claims (5)

1. a montmorillonoid-containing solidifying agent that is used to administer heavy-metal contaminated soil is characterized in that the weight percent of described solidifying agent is: cement 25-40%, polynite 40%-65%, unslaked lime 10%-20%.
2. a kind of montmorillonoid-containing solidifying agent that is used to administer heavy-metal contaminated soil according to claim 1 is characterized in that the weight percent of described solidifying agent is: cement 30-40%, polynite 40%-60%, unslaked lime 10%-15%.
3. a kind of montmorillonoid-containing solidifying agent that is used to administer heavy-metal contaminated soil according to claim 1 is characterized in that the weight percent of described solidifying agent is: cement 30%-40%, polynite 50%-55%, unslaked lime 10%-15%.
4. according to claim 1,2 or 3 described a kind of montmorillonoid-containing solidifying agent that are used to administer heavy-metal contaminated soil, the using method that it is characterized in that described solidifying agent is: described solidifying agent is added directly to heavy-metal contaminated soil and mixing, and adding proportion is the 10%-20% of contaminated soil weight.
5. according to claim 1,2 or 3 described a kind of montmorillonoid-containing solidifying agent that are used to administer heavy-metal contaminated soil, it is characterized in that: described solidifying agent is used for the improvement of lead pollution of soil.
CN2010102884808A 2010-09-21 2010-09-21 Montmorillonite-containing curing agent used for treating heavy metal contaminated soil Pending CN101962554A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102989741A (en) * 2012-11-20 2013-03-27 盐城工学院 Preparation method of heavy metal solid waste curing agent
CN104478058A (en) * 2014-11-04 2015-04-01 沈礼群 Pond-lake heavy-metal pesticide fertilizer pollutant solidifying removing agent and preparation method thereof
CN111299315A (en) * 2020-03-13 2020-06-19 陕西地建土地工程技术研究院有限责任公司 Application of argillaceous shale and method for repairing lead and other heavy metal contaminated soil by utilizing argillaceous shale
CN115477520A (en) * 2022-10-14 2022-12-16 中国人民解放军63653部队 Composite material for sand solidification and preparation method and application thereof

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007268513A (en) * 2006-03-06 2007-10-18 Kobe Steel Ltd Method for treating waste
CN101722184A (en) * 2009-12-07 2010-06-09 中国科学院南京土壤研究所 Montmorillonoid in-situ remediation method for heavy metal contaminated soil

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007268513A (en) * 2006-03-06 2007-10-18 Kobe Steel Ltd Method for treating waste
CN101722184A (en) * 2009-12-07 2010-06-09 中国科学院南京土壤研究所 Montmorillonoid in-situ remediation method for heavy metal contaminated soil

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102989741A (en) * 2012-11-20 2013-03-27 盐城工学院 Preparation method of heavy metal solid waste curing agent
CN102989741B (en) * 2012-11-20 2015-05-27 盐城工学院 Preparation method of heavy metal solid waste curing agent
CN104478058A (en) * 2014-11-04 2015-04-01 沈礼群 Pond-lake heavy-metal pesticide fertilizer pollutant solidifying removing agent and preparation method thereof
CN104478058B (en) * 2014-11-04 2016-03-30 沈礼群 A kind of Gou Tang lake heavy metal agriculture chemical pollutes solidification remover and preparation method thereof
CN111299315A (en) * 2020-03-13 2020-06-19 陕西地建土地工程技术研究院有限责任公司 Application of argillaceous shale and method for repairing lead and other heavy metal contaminated soil by utilizing argillaceous shale
CN111299315B (en) * 2020-03-13 2022-04-26 陕西地建土地工程技术研究院有限责任公司 Method for repairing lead heavy metal contaminated soil by argillaceous shale
CN115477520A (en) * 2022-10-14 2022-12-16 中国人民解放军63653部队 Composite material for sand solidification and preparation method and application thereof
CN115477520B (en) * 2022-10-14 2023-09-22 中国人民解放军63653部队 Composite material for sand solidification and preparation method and application thereof

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Application publication date: 20110202