ASTM D6161-05

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D6161 – 05
Standard Terminology
Used for Microfiltration, Ultrafiltration, Nanofiltration and
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Reverse Osmosis Membrane Processes
This standard is issued under the fixed designation D6161; 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 accumulator—a pulsation dampener installed on the suction
and/or discharge lines of pumps, generally plunger type, to
1.1 This terminology covers the use of microfiltration,
minimize pressure surges and provide uniformity of flow.
ultrafiltration,nanofiltrationandreverseosmosisformembrane
accuracy—the closeness of agreement between an observed
separation processes.
value and an accepted reference value. Where an accepted
2. Referenced Documents reference value is not available, accuracy is a description of
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a measure of the degree of conformity of a value generated
2.1 ASTM Standards:
by a specific procedure to the assumed or accepted true
D1129 Terminology Relating to Water
value, including both precision and bias.
D2035 Practice for Coagulation-Flocculation Jar Test of
acidity—the quantitative capacity of aqueous media to react
Water
with hydroxyl ions.
D3739 Practice for Calculation and Adjustment of the
activated carbon—granulated or powdered activated carbon
Langelier Saturation Index for Reverse Osmosis
usedtoremovetastes,odor,chlorine,chloramines,andsome
D4582 Practice for Calculation andAdjustment of the Stiff
organics from water. A family of carbonaceous substances
and Davis Stability Index for Reverse Osmosis
manufactured by processes that develop adsorptive proper-
3. Significance and Use
ties.
adsorption—the holding of a substance onto the surface of a
3.1 The need to understand the relationships found in
solid by chemical surface forces, without forming new
membraneunitprocessesforwatertreatmentincreaseswiththe
chemical bonds.
continuing demand for these separation systems. Defining the
aerobic bacteria—bacteria that require oxygen for growth.
terms common to microfiltration, ultrafiltration, nanofiltration
See bacteria, aerobes.
andreverseosmosisprocessesassistthemanufacturer,consult-
aggregate—granular material such as sand, gravel, crushed
ant and end-user in eliminating inter-process terminology
stone.
confusion. This standard expands the definitions found in
airheader—the pipe running within a cassette that distributes
Terminology D1129.
the air to the individual modules or aerators.
4. Terminology
airscour—distributingairovertheentireareaatthebottomof
a filter media flowing upward or immersed membrane to
4.1 Definitions:
improve the effectiveness of filtration or backwashing or to
absolute filter rating—particle size above which 100 % of
permit the use of lower backwash water flow rate, or both.
particles that are trapped on or within the filter medium.
air stripping—removal of volatile substances from a water
absorption—the release for desorption holding of a substance
solution by passing a gas through the solution.
within a solid by cohesive or capillary forces.
algae—a major group of lower plants, generally aquatic,
photosynthetic of extremely varied morphology and physi-
ology, mono cellular plants with chlorophyll often masked
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This terminology is under the jurisdiction ofASTM Committee D19 on Water by a brown or red pigment.
and is the direct responsibility of Subcommittee D19.08 on Membranes and Ion
alkalinity—thequantitativecapacityofaqueousmediatoreact
Exchange Materials.
with hydrogen ions. “M” alkalinity is that which will react
CurrenteditionapprovedJune1,2005.PublishedJuly2005.Originallyapproved
with acid as the pH of the sample is reduced to the
in 1997. Last previous edition approved in 1998 as D6161–98. DOI: 10.1520/
D6161-05.
methylorange endpoint of about 4.5. “P” alkalinity is that
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
which reacts with acid as the pH of the sample is reduced to
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
the phenolphthalein end point of 8.3.“ M” is the total
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. alkalinity which is the sum of hydroxide, carbonate, and
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D6161 – 05
bicarbonate contents, “P” includes all the hydroxyl and half area of membrane per unit of net driving pressure (NDP);
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the carbonate content. units of measurement are m /hr/m /kPa.
alum—aluminum sulfate, AL (SO ) XH O (X = 14-18), a AWWA—American Water
...