ASTM D5886-95(2006)
(Guide)Standard Guide for Selection of Test Methods to Determine Rate of Fluid Permeation Through Geomembranes for Specific Applications
Standard Guide for Selection of Test Methods to Determine Rate of Fluid Permeation Through Geomembranes for Specific Applications
SIGNIFICANCE AND USE
The principal characteristic of geomembranes is their intrinsically low permeability to a broad range of gases, vapors, and liquids, both as single-component fluids and as complex mixtures of many constituents. As low permeable materials, geomembranes are being used in a wide range of engineering applications in geotechnical, environmental, and transportation areas as barriers to control the migration of mobile fluids and their constituents. The range of potential permeants is broad and the service conditions can differ greatly. This guide shows users test methods available for determining the permeability of geomembranes to various permeants.
The transmission of various species through a geomembrane is subject to many factors that must be assessed in order to be able to predict its effectiveness for a specific service. Permeability measurements are affected by test conditions, and measurements made by one method cannot be translated from one application to another. A wide variety of permeability tests have been devised to measure the permeability of polymeric materials; however, only a limited number of these procedures have been applied to geomembranes. Test conditions and procedures should be selected to reflect actual service requirements as closely as possible. It should be noted that field conditions may be difficult to model or maintain in the laboratory. This may impact apparent performance of geomembrane samples.
This guide discusses the mechanism of permeation of mobile chemical species through geomembranes and the permeability tests that are relevant to various types of applications and permeating species. Specific tests for the permeability of geomembranes to both single-component fluids and multicomponent fluids that contain a variety of permeants are described and discussed.
SCOPE
1.1 This guide covers selecting one or more appropriate test methods to assess the permeability of all candidate geomembranes for a proposed specific application to various permeants. The widely different uses of geomembranes as barriers to the transport and migration of different gases, vapors, and liquids under different service conditions require determinations of permeability by test methods that relate to and simulate the service. Geomembranes are nonporous homogeneous materials that are permeable in varying degrees to gases, vapors, and liquids on a molecular scale in a three-step process (1) by dissolution in or absorption by the geomembrane on the upstream side, (2) diffusion through the geomembrane, and (3) desorption on the downstream side of the barrier.
1.2 The rate of transmission of a given chemical species, whether as a single permeant or in mixtures, is driven by its chemical potential or in practical terms by its concentration gradient across the geomembrane. Various methods to assess the permeability of geomembranes to single component permeants, such as individual gases, vapors, and liquids are referenced and briefly described.
1.3 Various test methods for the measurement of permeation and transmission through geomembranes of individual species in complex mixtures such as waste liquids are discussed.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D5886 – 95 (Reapproved 2006)
Standard Guide for
Selection of Test Methods to Determine Rate of Fluid
Permeation Through Geomembranes for Specific
Applications
This standard is issued under the fixed designation D5886; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope D814 Test Method for Rubber Property—Vapor Transmis-
sion of Volatile Liquids
1.1 Thisguidecoversselectingoneormoreappropriatetest
D815 Method of Testing Coated Fabrics Hydrogen Per-
methods to assess the permeability of all candidate geomem-
meance
branes for a proposed specific application to various per-
D1434 Test Method for Determining Gas Permeability
meants.Thewidelydifferentusesofgeomembranesasbarriers
Characteristics of Plastic Film and Sheeting
to the transport and migration of different gases, vapors, and
D4439 Terminology for Geosynthetics
liquids under different service conditions require determina-
D4491 Test Methods for Water Permeability of Geotextiles
tionsofpermeabilitybytestmethodsthatrelatetoandsimulate
by Permittivity
the service. Geomembranes are nonporous homogeneous ma-
E96/E96M Test Methods for Water Vapor Transmission of
terials that are permeable in varying degrees to gases, vapors,
Materials
and liquids on a molecular scale in a three-step process (1)by
F372 Test Method for Water Vapor Transmission Rate of
dissolution in or absorption by the geomembrane on the
Flexible Barrier Materials Using an Infrared Detection
upstream side, (2) diffusion through the geomembrane, and (3)
Technique
desorption on the downstream side of the barrier.
F739 Test Method for Permeation of Liquids and Gases
1.2 The rate of transmission of a given chemical species,
through Protective Clothing Materials under Conditions of
whether as a single permeant or in mixtures, is driven by its
Continuous Contact
chemical potential or in practical terms by its concentration
gradient across the geomembrane. Various methods to assess
3. Terminology
the permeability of geomembranes to single component per-
3.1 Definitions:
meants, such as individual gases, vapors, and liquids are
3.1.1 downstream, n—the space adjacent to the geomem-
referenced and briefly described.
brane through which the permeant is flowing.
1.3 Varioustestmethodsforthemeasurementofpermeation
3.1.2 geomembrane, n—an essentially impermeable geo-
and transmission through geomembranes of individual species
synthetic composed of one or more synthetic sheets. (See
in complex mixtures such as waste liquids are discussed.
Terminology D4439.)
1.4 This standard does not purport to address all of the
3.1.2.1 Discussion—In geotechnical engineering, essen-
safety concerns, if any, associated with its use. It is the
tially impermeable means that no measurable liquid flows
responsibility of the user of this standard to establish appro-
through a geosynthetic when tested in accordance with Test
priate safety and health practices and determine the applica-
Methods D4491.
bility of regulatory limitations prior to use.
3.1.3 geosynthetic, n—a planar product manufactured from
2. Referenced Documents polymeric material used with soil, rock, earth, or other geo-
technical engineering-related material as an integral part of a
2.1 ASTM Standards:
man-made project, structure, or system. (See Terminology
D471 Test Method for Rubber Property—Effect of Liquids
D4439.)
3.1.4 permeability, n—the rate of flow under a differential
ThisguideisunderthejurisdictionofASTMCommitteeD35onGeosynthetics
pressure, temperature, or concentration of a gas, liquid, or
and is the direct responsibility of Subcommittee D35.10 on Geomembranes.
vapor through a material. (Modified from Test Methods
Current edition approved June 1, 2006. Published June 2006. Originally
D4491.)
approved in 1995. Last previous edition approved in 2001 as D5886–95 (2001).
DOI: 10.1520/D5886-95R06.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on Withdrawn. The last approved version of this historical standard is referenced
the ASTM website. on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D5886 – 95 (2006)
3.1.5 permeant, n—achemicalspecies,gas,liquid,orvapor geomembranes, but the ions are not transmitted. Thus, the
that can pass through a substance. water that is transmitted through a hole-free geomembrane
does not carry dissolved inorganics. The direction of perme-
4. Summary of Guide
ation of a component in the mixture is determined thermody-
namically by its chemical potential difference or concentration
4.1 The wide range of uses of geomembranes as barriers in
gradient across the geomembrane. Thus the water in the
many different environments to many different permeating
wastewaterontheupstreamsideisatalowerpotentialthanthe
species requires different test procedures to assess the effec-
less contaminated water on the downstream side and can
tiveness of a given membrane for a given application. The
permeate the geomembrane into the wastewater by osmosis.
permeating species range from a single component to highly
4.1.2 Although inorganic salts do not permeate geomem-
complex mixtures such as those found in waste liquids and
branes, some organic species do. The rate of permeation
leachates. In specialized applications, service it may be impor-
through a geomembrane depends on the solubility of the
tant to measure transmission or migration of a species that
organicinthegeomembraneandthediffusibilityoftheorganic
would take place under specific conditions and environments
in the geomembrane as driven by the chemical potential
including temperature, vapor pressure, and concentration gra-
gradient. Principle factors that can affect the diffusion of an
dients. Tests that would be applicable to the measurement of
organic within a geomembrane include:
the permeability of a material to different permeants present in
4.1.2.1 The solubility of the permeant in the geomembrane,
various applications are summarized in Table 1.
4.1.2.2 The microstructure of the polymer, for example,
4.1.1 In the use of geomembranes in service as barriers to
percent crystallinity,
the transmission of fluids, it is essential to recognize the
4.1.2.3 Whether the condition at which diffusion is taking
difference between geomembranes that are nonporous homo-
place is above or below the glass transition temperature of the
geneous materials and other liner materials that are porous,
such as soils and concretes. The transmission of permeating polymer,
4.1.2.4 The other constituents in the geomembrane com-
species through geomembranes without holes proceeds by
absorption of the species in the geomembrane and diffusion pound,
4.1.2.5 Variation in manufacturing processes,
through the geomembrane on a molecular basis. The driving
force is chemical potential across the geomembrane. A liquid 4.1.2.6 The flexibility of the polymer chains,
4.1.2.7 The size and shape of the diffusing molecules,
permeates porous materials in a condensed state that can carry
the dissolved constituents, and the driving force for such 4.1.2.8 The temperature at which diffusion is taking place,
permeationishydraulicpressure.Duetotheselectivenatureof and
geomembranes,thepermeationofthedissolvedconstituentsin 4.1.2.9 The geomembrane.
liquids can vary greatly, that is, components of a mixture can 4.1.3 The movement through a hole-free geomembrane of
permeate at different rates due to differences in solubility and mobile species that would be encountered in service would be
diffusibility in a given geomembrane. With respect to the affected by many factors, such as:
inorganic aqueous salt solution, the geomembranes are semi- 4.1.3.1 The composition of the geomembrane with respect
permeable, that is, the water can be transmitted through the to the polymer and to the compound,
TABLE 1 Applicable Test Method for Measuring Permeability of Geomembranes to Various Permeants
Applicable Test Method and Permeant
Fluid Being Contained Example of Permeant Example of Field Application
Detector and Quantifier
Single-Component Fluids:
Gas H ,O Barriers, pipe, and hose liners D815
2 2
N ,CH D1434-V
2 4
CO D1434-P
Water vapor H O Moisture vapor barriers, water reservoir E96/E96M, D653
covers
Liquid water H O Liners for reservoirs, dams, and canals Soil-type permeameter with hydraulic
pressure
Organic vapor Organic species Secondary containment for organic D814, E96/E96M, F372
solvent and gasoline
Organic liquid Organic solvents species Containers, tank liners secondary D814, E96/E96M
containment
Multicomponents Fluids:
Gases CO /CH Barriers, separation of gases F372, GC, GCMS
2 4
Aqueous solutions of inorganic, for Ions, salts Pond liners Pouch, osmotic cell, ion analysis
example, brines, incinerator ash
leachates, leach pad leachate
Mixtures of organics, spills, Organic species Liners for tanks and secondary E96/E96M with headspace, GC
hydrocarbon fuels containment
Aqueous solutions of organics Organic species, H O Liners for ponds and waste disposal Pouch, Multi-compartment cell with
analysis by GC on GCMS
Complex aqueous solutions of organics H O, organic species, dissolved salts Liners for waste disposal Pouch, Multi-compartment cell, osmotic
and inorganic species cell, analysis by head-space GC
D5886 – 95 (2006)
4.1.3.2 The thickness of the geomembrane, canpermeateageomembraneonamolecularlevel.Thus,even
4.1.3.3 The service temperature, if a geomembrane is free of macroscopic holes, some compo-
4.1.3.4 The temperature gradient across the geomembrane nentsofthecontainedfluidcanpermeateandmightescapethe
in service, containment unit.
4.1.3.5 The chemical potential across the geomembrane, 6.2 The basic mechanism of permeation through geomem-
that includes pressure and concentration gradient, branes is essentially the same for all permeating species. The
4.1.3.6 The composition of the fluid and the mobile con- mechanism differs from that through porous media, such as
stituents, soils and concrete, which contain voids that are connected in
4.1.3.7 The solubility of various components of an organic such a way that a fluid introduced on one side will flow from
liquid in the particular geomembrane that increase concentra- void to void and emerge on the other side; thus, a liquid can
tion of individual components on the upstream side of the flow through the voids and carry dissolved species.
geomembrane and can cause swelling of the geomembrane 6.3 Overall rate of flow through saturated porous media
resulting in increased permeability, follows Darcy’s equation that states that the flow rate is
4.1.3.8 The ion concentration of the liquid, and proportional to the hydraulic gradient, as is shown in the
4.1.3.9 Abilityofthespeciestomoveawayfromthesurface following equation:
on the downstream side.
Q 5 kiA (1)
4.1.4 Because of the great number of variables, it is impor-
tant to perform permeability tests of a geomembrane under where:
Q = rate of flow,
conditions that simulate as closely as possible the actual
k = constant (Darcy’s coefficient of permeability),
environmentalconditionsinwhichthegeomembranewillbein
A = total inside cross-sectional area of the sample con-
service.
tainer, and
5. Significance and Uses i = hydraulic gradient.
6.4 With most liquids in saturated media, the flow follows
5.1 The principal characteristic of geomembranes is their
Darcy’s equation; however, the flow can deviate due to
intrinsicallylowpermeabilitytoabroadrangeofgases,vapors,
interactions between the liquid and the surface of the soil
and liquids, both as single-component fluids and as complex
particles.Theseinteractionsbecomeimportantintheescapeof
mixtures of many constituents. As low permeable materials,
dissolved species through a low-permeability porous liner
geomembranes are being used in a wide range of engineering
system in a waste facility. Dissolved chemical species, either
applicationsingeotechnical,environmental,andtransportation
organic or inorganic, not only can permeate such a medium
areas as barriers to control the migration of mobile fluids and
advectively (that is, the liquid acts as the carrier of the
their constituents. The range of potential permeants is broad
chemical species), but also by diffusion in accordance with
and the service conditions can differ greatly. This guide shows
Fick’s two laws of diffusion.
users test methods available for determining the permeability
6.5 Even though polymeric geomembranes are manufac-
of geomembranes to various permeants.
tured as solid homogeneous nonporous materials, they contain
5.2 The transmission of various species through a geomem-
interstitial spaces between the polymer molecules through
brane is subject to many factors that must be assessed in order
which small molecules can diffuse. Thus, all polymeric
to be able to predict its effectiveness for a specific service.
geomembranesarepermeabletoadegree.Apermeantmigrates
Permeabilitymeasurementsareaffectedbytestconditions,and
throughthegeomembraneonamolecularbasisbyanactivated
measurements made by one method cannot be translated from
diffusion process and not as a liquid. This transport process of
oneapplicationtoanother.Awidevarietyofpermeabilitytests
chemical species involves three steps:
have been devised to measure the permeability of polymeric
6.5.1 The solution or absorption of the permeant at the
materials; however, only a limited number of these procedures
upstream surface of the geomembrane,
have been applied to geomembranes. Test conditions and
6.5.2 Diffusion of the dissolved species through the
procedures should be selected to reflect actual service require-
geomembrane, and
ments as closely as possible. It should be noted that field
6.5.3 Evaporation or desorption of the permeant at the
conditions may be difficult to model or maintain in the
downstream surface of the geomembrane.
laboratory.Thismayimpactapparentperformanceofgeomem-
6.6 The driving force for this type of activated permeation
brane samples.
process is the “activity” or chemical potential of the permeant
5.3 This guide discusses the mechanism of permeation of
that is analogous to mechanical potential and electrical poten-
mobile chemical species through geomembranes and the per-
tial in other systems. The chemical potential of the permeant
meabilityteststhatarerelevanttovarioustypesofapplic
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.