Upload
trinhque
View
218
Download
0
Embed Size (px)
Citation preview
IntroductionIntroduction
Chemical Resistance of Geosynthetic Polymers to Hydrocarbons and Toxic Soil Contaminants
Presented by Charlotte Shaw
© Industrial Textiles & Plastics Ltd.
Presented by Charlotte Shaw
ObjectiveObjective
� Improve understanding of:• Chemical resistance• How a polymer’s chemical resistance
depends upon its molecular structure• Chemical resistance Standards & Test
Methods
© Industrial Textiles & Plastics Ltd.
• Limitations of current test methods• New Technologies to improve chemical
resistance
Geosynthetic MaterialsGeosynthetic Materials
� PVC polyvinyl chloride� Butyl Rubber polyisobutylene / PIB� EDPM ethylene propylene diene monomer� CSPE chlorosulphonated polyethylene [HypalonTM]� CR polychloroprene [NeopreneTM ]� PP polypropylene
© Industrial Textiles & Plastics Ltd.
� PP polypropylene� LDPE low density polyethylene� HDPE high density polyethylene� EIA ethylene interpolymer alloy
[ CoolgardTM, XR-5TM, UltraTechTM, ElvaloyTM ]� Aluminium Laminates
Geosynthetic MaterialsGeosynthetic Materials
� Limited Chemical Resistance Information• Industry practice to compile
resistance charts• Information often sparse and
qualitative
© Industrial Textiles & Plastics Ltd.
• Do not provide any performance data
Geosynthetic MaterialsGeosynthetic Materials
Category Group Subgroup Compound
Membrane Material
PV
C
But
yl
ED
PM
CS
PE
Neop
rene
PP
PC
LDP
E
HD
PE
EIA
PURA
FLEX
Aromatics
Benzene Derivatives
Benzene
Benzyl chloride ND
ND ND
BiphenylND
ND ND
Dichlorobenzene ND
Toluene
Ethylbenzene
Stryene
Xylenes
PolycyclicAromaticHydrocarbons(PAH)
Nitrobenzene
Acenaphthene ND
ND ND ND ND ND ND ND ND ND
Anthracene ND
ND ND ND ND ND ND ND ND ND
Benzo(a)anthracene ND
ND ND ND ND ND ND ND ND ND
Benzo(a)pyrene ND
ND ND ND ND ND ND ND ND ND
Benzo( b)fluorantheneND
ND ND ND ND ND ND ND ND ND
Benzo(k)fluorantheneND
ND ND ND ND ND ND ND ND ND
Dibnezo(a,h)anthracene ND
ND ND ND ND ND ND ND ND ND
Fluoranthene ND
ND ND ND ND ND ND ND ND ND
FluoreneND
ND ND ND ND ND ND ND ND ND
Indeno(1,2,3-cd)pyreneND
ND ND ND ND ND ND ND ND ND
Naphthalene ND
Butane ND
Ethane ND ND ND ND
Category Group Subgroup Compound
Membrane Material
PV
C
But
yl
ED
PM
CS
PE
Neo
pren
e
PP
PC
LDP
E
HD
PE
EIA
PURA
FLEX
Acids
Organics
Acetic acid
Acetic Anhydride
Butyl Acetate
Ethyl Acetate
Inorganics
Benzoic Acid
Carbonic Acid
Hydrochloric Acid
Perchloric Acid ND ND ND
Carbohydrates Starch
InorganicCompounds
CarbonsCarbon Dioxide
Carbon Monoxide
Chlorines Aqueous
Gaseous
Alkalis
Calcium Carbonate
Magnesium Carbonate
Sodium Carbonate
Hydroxides
Calcium Hydroxide
Magnesium Hydroxide
Sodium Hydroxide
Bromides Bromine (liquid)
Fluorines Elemental
Iodines Elemental
Nitrogen Gaseous
Oxygen Elemental
© Industrial Textiles & Plastics Ltd.
Hydrocarbons
Aliphatics
Alkanes
Hexane
Methane ND
Pentane ND
Propane ND
Octane ND
Heptane
Kerosene
Isoprene ND ND
Cyclohexane
Alkenes Butene ND ND
Alkynes Acetylene
Halogenated
Brominated Bromoform
Chlorinated
Carbon Tetrachloride ND
Chloroform
Dichloroethane
Tetrachloroethane
Trichloroethylene
Fluorocarbons Freon 12
Freon 22
Iodinated Iodoform
Generic Oils & Fuels
Mineral Oil
Crude Oil
Petroleum Oil
Diesel
Hetrocyclics
Dioxan (1,4) ND ND
Morpholine ND ND ND
Pyridine
Tetrahydrofuran
Oxygen Elemental
Salt Brine
Silicone Oil
Sulphurs Copper Sulphate
Zinc Sulphide ND
Tin Stannous Chloride
OrganicCompounds
Lipids
Fats Fatty acids
OilsAnimal and Vegetable
Turpentine
Alcohols
Amyl
Benzyl
Butyl
Ethyl
Isopropyl
Methyl
Aldehydes
Acetaldehyde
Benzaldehyde ND
Formaldehyde
Amines Aniline
Cynides Copper Cyanide ND
Sodium Cyanide ND
Ethers Diethyl Ether
MTBE ND ND ND ND ND ND ND
Ketones Acetone
Methyl Isopropyl Ketone ND
Organometallics
Ferric Chloride ND
Ferric Nitrate ND
Ferric Sulphate
Phenols
Carbolic Acid
Cresols
Tannic Acid
Urea
Rating Index
Resistant
Limited Effect (at elevated temperature or high concentration)
Not Resistant
ND No Data
Test MethodsTest Methods
� EN 13361 Reservoirs & Dams� EN 13362 Canals� EN 13491 Tunnels & Underground
Structures� EN 13492 Liquid Waste� EN 13493 Solid Waste
© Industrial Textiles & Plastics Ltd.
� EN 13493 Solid Waste
• Define mechanical performance and• Defines chemical resistance testing to:
EN 14414 & EN 14415
Test MethodsTest Methods
� EN 14414 Chemical Resistance to Leachates and Aggressive Chemicals• Method A – Acids• Method B – Alkalis• Method C – Hydrocarbons
(diesel fuel, paraffin, lubricating oil)• Method D – Synthetic leachate
© Industrial Textiles & Plastics Ltd.
• Method D – Synthetic leachate
� EN 14415 Resistance to Leaching• Method A – Hot water• Method B – Alkalis• Method C – Organic solvents
(methanol, isopropanol & glycol)
Test MethodsTest Methods
� EN 14414 and EN 14415 Test Procedure• Immersion test • 50 ºC for 56 days• Visual inspection• Measurements of Tensile Strength &
Elongation variances
© Industrial Textiles & Plastics Ltd.
Elongation variances• Pass criterion is merely
residual strength >75%
* Test Procedures equivalent to ASTM D5322 within EPA method 9090 and ASTM D5747.
Chemical Resistance Chemical Resistance -- CharacterisedCharacterised
� Molecular structure characteristics• Molecular Weight
- Chain length is directly related to polymer strength
• Molecular Weight Distribution- Relationship between the number of
© Industrial Textiles & Plastics Ltd.
- Relationship between the number of species and the molar mass
• Crystallinity- Ratio of amorphous regions to crystalline regions within the polymer’s structure
• Polarity- Distribution of electrons
Chemical Resistance Chemical Resistance -- MaterialsMaterials
LDPEHDPE
© Industrial Textiles & Plastics Ltd.
PP PVC
Chemical Resistance Chemical Resistance -- MaterialsMaterials
Polymer HDPE LDPE PP PVC
Crystallinity % 55-65 30-45 40-45 0
© Industrial Textiles & Plastics Ltd.
Tensile Strength Good Fair Good Poor
Brittle Deformation Poor Good Fair Excellent
Chemical Resistance Good Fair Good Poor
Polarity Non-Polar Non-Polar Non-Polar Polar
Chemical Resistance Chemical Resistance -- PolarityPolarity
� Polar & Non-polar Chemicals• Normally an atom has an even distribution of electrons in the
orbits• If more end up on one side that the other in a molecule, there is
a resulting electrical field in that area
Polar Non-polar
© Industrial Textiles & Plastics Ltd.
H2O CO2
Polar Non-polar
Chemical Resistance Chemical Resistance -- SolubilitySolubility
� General rule• Polar + Polar = Soluble• Non-polar + Non-polar = Soluble• Polar + Non-polar = Not Soluble
e.g. Water (Polar) + Oil (Non-Polar)� Why is this significant?
© Industrial Textiles & Plastics Ltd.
� Why is this significant?
Methanol (Polar) Hydrocarbons (Non-polar)
HDPE (Non-polar)
Geosynthetic MaterialsGeosynthetic Materials
� PVC polyvinyl chloride Polar� Butyl Rubber polyisobutylene / PIB Non-Polar� EDPM ethylene propylene diene monomer Non-Polar� CSPE chlorosulphonated polyethylene Polar
[HypalonTM]� CR polychloroprene [NeopreneTM] Polar
© Industrial Textiles & Plastics Ltd.
� CR polychloroprene [NeopreneTM] Polar� PP polypropylene Non-Polar� LDPE low density polyethylene Non-Polar� HDPE high density polyethylene Non-Polar� EIA ethylene interpolymer alloy Polar
[ CoolgardTM, XR-5TM, UltraTechTM, ElvaloyTM ]
Chemical ResistanceChemical Resistance
� Solubility Parameters• Graphical representation• Green Sphere = polymer• Red Satellites = challenge chemicals
� The closer the challenge chemical is to the
© Industrial Textiles & Plastics Ltd.
� The closer the challenge chemical is to the polymer
• > Solubility• > Permeation rate
δD Dispersion Solubility ParameterδH Hydrogen Bonding Solubility ParameterδP Polar Solubility Parameter
Key Points Key Points –– Materials & TestsMaterials & Tests
� Common Geosynthetic Materials• Limited chemical resistance of mono-
polymer membrane materials� Current Test Methods
• Immersion testing measures a membrane’s Resilience, i.e. the effect of the challenge chemical on the
© Industrial Textiles & Plastics Ltd.
of the challenge chemical on the membrane’s physical characteristics
• Limited scope of challenge chemicals• Lack of Quantitative chemical
resistance data, i.e. no measure of performance.
Performance measured by Permeation
PermeationPermeation
21 3
© Industrial Textiles & Plastics Ltd.
1 SorptionPartitioning of the chemical to the liner governed by Henry’s Law :
Cg = Sgf*C
2 DiffusionMigration on a molecular scale through the barrier expressed by Fick’s first Law :
f = -Dg* (dcg / dz)
3 DesorptionPartitioning between the chemical and the outer surface of the barrier
PermeationPermeation
� Permeation Test Method• Each challenge chemical exposed to
the sample in a permeation cell• Sweep gas to mass spectrometer
© Industrial Textiles & Plastics Ltd.
Permeation Comparisons Permeation Comparisons -- materialsmaterials
HDPE 1.5mm
Butyl 1.5mm
EPDM 1.5mm
PVC 1.5mm
CSPE 1.5mm
Polychloroprene (CR) 1.5mm
© Industrial Textiles & Plastics Ltd.
0.00E+00 2.00E+02 4.00E+02 6.00E+02 8.00E+02 1.00E+03 1.20E+03 1.40E+03
Puraflex 0.45mm
HDPE 1.5mm
Puraflex 0.45mm
HDPE 1.5mm Butyl 1.5mm EPDM 1.5mm PVC 1.5mm CSPE 1.5mmPolychloropre
ne (CR) 1.5mm
Vinyl Chloride 1.67E-01 1.84E+03 6.15E+03 4.92E+03 6.15E+03 6.15E+02 4.92E+03
Methyl Isopropyl Ketone (MIK) 9.43E+00 8.05E+02 2.68E+03 2.15E+03 2.68E+03 2.69E+02 2.15E+03
Hexane 1.56E-06 5.37E+02 1.79E+03 1.43E+03 5.59E+02 1.79E+02 5.01E+02
Fluorene 3.23E-06 1.41E+02 4.69E+02 3.75E+02 4.69E+02 4.69E+01 3.75E+02
Benzene 3.52E-04 5.69E+02 1.90E+03 1.52E+03 1.90E+03 1.90E+02 1.52E+03
Aluminium Laminates Aluminium Laminates
� Aluminium laminates often sold as ‘barrier’ membranes• Products are generally Aluminium
laminated to LDPE or Bitumen• Developed as a Methane barrier• Fails EN 14414 A (sulphuric acid)7 days
© Industrial Textiles & Plastics Ltd.
• Unsuitable for moist soils, acidic soils or wherever there is any risk of acid rain
� Aluminium oxidises rapidly• Increases ‘wicking’• Delamination of membrane• Barrier properties negated
14 days
TechnologyTechnology
� Barrier Technology • Extruded multi-layer composite• Incorporates Polar and Non-polar layers
(> 5 layers and > 5 polymers)• Chemical Resistant core• Thermally weldable
© Industrial Textiles & Plastics Ltd.
• Thermally weldable
TechnologyTechnology
� Composite construction� Polar and Non-polar polymers� Resistant to Non-Polar and Polar challenge
chemicals
© Industrial Textiles & Plastics Ltd.
Polar (Methanol) Non-Polar (Hydrocarbons)
Non-polar
Polar
Non-polar
Installation Installation
� Installation• Compatible with existing installation
methods• Conventional geosynthetic membrane
welding equipment• Typically a Leister Twinny S hot air
wedge welder
© Industrial Textiles & Plastics Ltd.
wedge welder• BS EN 13067 Qualified Installers
recommended• Rapid 4m/min installation• Protected in accordance with
EN 13719
PuraflexPuraflex Testing Testing SummarySummary
� Passes Industry Chemical Resistance Tests• Immersion Tests• ASTM D5322 test method is common
to EPA Method 9090, ASTM D5647, EN BS 14414 & EN BS 14415
• EN BS tests limited to ‘cocktail’
© Industrial Textiles & Plastics Ltd.
• EN BS tests limited to ‘cocktail’ immersion tests (only 3 Hydrocarbons)
� Additional Puraflex Test Data• Immersion tests for further
Hydrocarbons (as identified in risk assessment)
and• Permeation data for 200 hydrocarbons
PuraflexPuraflex Permeation ModellerPermeation Modeller
� Permeation Modeller Software • Specifically written for environmental
consultants, hydro-geologists & geotechnical engineers
• Upload soil analysis concentrations• Enter variables
© Industrial Textiles & Plastics Ltd.
• Enter variables• Output permeation rates • Risk Assessment Models (e.g.CLEA)
ReferencesReferences
� ASTM D5322. Laboratory Immersion Procedures for evaluating the ChemicalResistance of Geosynthetics to liquids.
� ASTM D5747. Tests to Evaluate Chemical Resistance of Geomembranes toLiquids.
� CLAIRE Report. The soil generic assessment criteria for human health riskassessment.
� Bromwich.D.W The design of permeation cells for testing chemical protectiveclothing (1999). Phd Thesis – Griffith University.
� EN 14414 Geosynthetics – Screening test method for determining chemical
© Industrial Textiles & Plastics Ltd.
resistance for landfill applications (2004).� EN 14415 Geosynthetics barriers – Test methods for determining the resistance
to leaching (2004).� Lampman.S.W. Characterization and failure analysis of plastics (2003). ASM
International.� Method 9090A. Compatibility test for Wastes and Membrane Liners.� Sangam.H.P. & Rowe.R.K. Migration of dilute aqueous organic pollutants
through a HDPE geomembrane (2001). Geotextiles and Geomembranes, 19 pp329 – 357.
� Scheirs.J. A guide to polymeric geomembranes: A practical approach (2009).Wiley.