Treatment Technology for Pops

8/3/2019 Treatment Technology for Pops

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Treatmenttechnology for

popsBy: Ruby Anne Vega


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What is POPs?} Persistent Organic Pollutants} Synthetic chemicals with the ff. properties:

} Toxic and has adverse effects on human andanimals.

} Chemically stable and does not readily degradein the environment

} Lipophillic (have affinity for fats) and easily solublein fats

} Accumulate and biomagnify as they move up thefood chain

} Move over long distances in nature and can befound in regions far from their origin or point of use.


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Technologies fortreatment of pops


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Incineration} Subjects solid and

liquid POPs to

temperature greaterthan 500 degreesCelsius in thepresence of oxygent.

} Causes volatilation,

combustion, anddestruction oforganic compounds


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Biomediation(Daramend & XENOREM)

} Refers to the use ofmicro organisms to

break downcomplex organiccontaminants intosimpler

compounds.


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Solvent extraction} Ex-situ process in which

contaminants are seperated

from soils, sludges, and

sediments, thus reducing thevolume of waste to be

treated.

} Contaminated soil or waste

material is bought into

contact with fluid that

selectively dissolvescontaminants.


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Vitrification(PACT, PLASCON, & Geomelt)

} Used to treat soil andsediment containing

organic, inorganic,and radioactivecontaminants.

} Uses heat to meltcontaminated soil orsediment.

} Forms a rigid, glossyproduct, causingreduction in volumeof treated soil.


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Solidification/stabilization

} Immobilization technologies

} Remediate soils and other

contaminated materials byreducing mobility ofcontaminants,

} Contaminated materials arecombined with variousadditives to reducecontaminant mobility

} Both are often employedtogether


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Solidification/stabilization

} Stabilization} Chemically limits the solubility or mobility of waste

contaminants, reduces leachability of wastes.} Does not change physical characteristics of waste

} Often applied to wastes containing a high fraction ofnon volatile organics, such as sludges.

} Solidification} Produces solid blocks of waste material with high

structural integrity and low permeability.


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Gas phase chemical reduction

} Mainly known as Eco Logicdeveloped in Canada

}

Alternative to incineration} Hydrogen reacts with

chlorinated organiccompounds at hightemperatures and lowpressure yielding primarilymethane and hydrogen

chloride.


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Alkali metal reduction(Sodium reduction)

} Uses metallic alkali, such as

sodium, to react with chlorine

int the halogenated non-aqueous waste to produce salt

and non-halogenated waste.

} Is an ex-situ technology and is

used only to treat

contaminated soil

} No mention of being utilized to

remediate soil.


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Pyrolysis and gasification

} Organic contaminants aredecomposed chemically byheat in an oxygen deprivedenvironment.

} Are operated with less thanstoichiometric quantities ofoxygen

} Degrades waste to producechar, pyrolysis oil, and

synthetic gas (syngas)


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Pyrolysis and gasification

} If volatile, semi volatilematerials are present in waste,

thermal desorption occurs.} Gasification

} Involves use of sub-stoichiometric amount ofoxygen, whereas pyrolysisuses none.

} Pyrolisis

} Capable of destroyingdioxins by decompositionand volatilization.


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Ball Milling/Mechano-ChemicalDehalogenation (MCD)

} Commercially known as MCD

} Treates high-stregnth wastecontaining POPs usingmechanical energy topromote reductivedehalogenation ofcontaminants.

} Developed by EnvironmentalDecontamination Ltd.


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Thermal DESORPTION

} Ex-situ treatment that usesdirect or indirect heat.

} Capable of treating variousmaterials, including soil,sediment, or sludge.

} 2 steps

} Heat is applied tocontaminated material tovaporize contaminants intogas

} Gas steam is collectedcondensed, and destroyed.

} Semi volatile Organiccompounds, and othercompounds with boiling

points above 300 degrees areprocessed through direct orindirect contact with thermaldesorption units.Contaminants with boilingpoints over 300 degreesCelsius are treated at higher-

temperature systems.


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Supercritical extraction (SCE)

} Based on supercritical fluidextraction of organiccompounds on from different

solid matrices for analyticalpurposes.

} Not yet beencommercialized.

} early efforts focused onextracting harmful organic

chemicals from spiked soilsusing supercritical carbondioxide.


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Soil Washing

} Uses physical or chemicaltechniques to separatecontaminants from soil and

sediments.

} Contaminants areconcentrated into smallervolumes and are recycled ordisposed.

} Wash water can consist of

water only or includesadditives.


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Chemical Dehalogenation

} Involves direct chemical strippingor halogen atoms from organics

in soils, sediments, and sludges.} Includes processes in which

} Chemical reagent is applied

} Reagent reacts with contaminantto cause removal of one or morehalogen atoms from molecule ofcontaminant.

} Reaction maybe substitution orelimination.


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Phytoremediation

} uses vegetation, enzymesderived from the vegetation, and

other complex processes, toisolate, destroy, transport, andremove organic pollutants fromcontaminated soils.

} Can be applied in crude oil,metals, explosives, pesticides,chlorinated solvents and

numerous other contaminants.} Takes advantage of natural plant

processes

Treatment Technology for Pops

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