Membrane Treatment

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Proton Antiscalant Software
membranechemicals.com/en/services/proton-antiscala
nt-software/
PROTON The Worlds Most Powerful Membrane
Antiscalant Software Why was AWCs new
antiscalant software named PROTON? Protonation
is the acceptance of acid protons from the
surrounding solution, while deprotonation is the
donation of acid protons to the surrounding
solution. The name PROTON was selected because
all the calculations in the software, whether for
scale saturation, or for salt rejection, are
based on protonation and deprotonation of weak
acids, bases and ion complexes in the Reverse
Osmosis/Nanofiltration (RO/NF) process. How can
PROTON help me with system design? PROTON
allows the user to compare the required feed
pressure and permeate water quality for various
membranes under identical conditions. Once the
design is selected, the user can simply select a
different membrane type, and can instantly see
the impact on pressure, water quality and
scaling potential. The user can see real time
impacts of changes in pH, temperature or
recovery on pressure, flux and permeate
quality. PROTON accurately calculates boron
rejection with varying pH, accounting for both
temperature and ionic strength, and
differentiating between rejection by
nanofiltration, brackish, and seawater
membranes. Other contaminant rejections that are
calculated include iron, manganese, aluminum,
ammonia, nitrate, nitrite, sulfides. It is also
the only software currently available that
predicts arsenic rejection with varying pH,
temperature and ionic strength. PROTON even
provides calculations that help with design of
pretreatment coagulation and post treatment
degasification (see below Chemical
Speciation). What makes PROTON different from
other antiscalant software? Most reverse osmosis
and nanofiltration antiscalant software assume
100 salt rejection. The few that allow entry of
the membrane salt rejection apply it as a factor,
completely ignoring the fact that salt passage
is a function of membrane flux.
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• PROTON is the first antiscalant software that
  can design a nanofiltration or reverse osmosis
  system, and account for membrane properties and
  flux rates at the various stages of a system.
  The user has the option of using the system
  design provided by PROTON, or overwriting it
  with the membrane manufacturers array and flow
  rates per stage. The software also calculates
  the concentration polarization factor, providing
  the user with the most accurate, and optimum
  scale inhibitor dosages required for NF, RO or
  NF/RO hybrid systems. The hybridization feature
  allows the user to enter any combination of
  membranes within the same stage. PROTON is also
  the only antiscalant projection software capable
  of modelling Desalitechs Closed Circuit Reverse
  Osmosis (CCRO) technology. CCRO is a unique
  technology that uncouples recovery, flux and
  crossflow to enable operation at recoveries well
  beyond those achievable with conventional RO.
• PROTON calculates the scaling potential for over
  50 different scales that can form in RO/NF
  membrane systems. Many RO antiscalant software
  programs use canned formulas that fail or give
  erroneous readings outside a certain pH or TDS
  range. However, Protons scaling calculations
  are not based on formulas but rather on
  thermodynamic data acquired from peer reviewed
  scientific research papers. Temperature, ion
  activity, and ion complexes are considered for
  every single calculation. The software accounts
  for over 130 ion complexes, allowing accurate
  modelling for complex industrial wastewater reuse
  or seawater at the entire RO operating range of
  1 11. The scaling saturations calculated by
  PROTON are therefore the most accurate and
  reliable in the industry with all reactions
  tested in a controlled environment and reconciled
  in real world applications.
• PROTON has also introduced five powerful new
  indices
• Calcium Carbonate Nucleation Index (CCNI) The
  CCNI is a calcium carbonate index that accounts
  for pH, temperature, ionic activity, and ion
  complex formation. In reverse osmosis and
  nanofiltration systems, any amount of calcium
  carbonate scale will impact performance. The
  commonly used Langelier Saturation Index (LSI) is
  limited in that it does not account for ion
  complex formation, and only estimates ionic
  activity by applying a fudge factor based on
  TDS. At higher TDS, the Stiff Davis index is
  often used, but is very unreliable when used for
  non-seawater applications. The Calcium Carbonate
  Precipitation Potential (CCPP) calculates the
  actual quantity of scale that can precipitate.
  But it is stoichiometrically limited, so that a
  higher driving force for scale formation can be
  masked by a low calcium concentration a water
  with a high driving force for scale formation and
  a non-scaling water can both have a CCPP of only
  125 mg/l simply because the calcium concentration
  is only 50 ppm in both. The CCNI is able to
  accurately predict spontaneous nucleation and
  saturation of calcium carbonate for any water
  quality in the pH range of 1 11 and
  temperature range of 5 60 C.
• Malki Kinetics Index (MKI) This is an index
  based on the rate of formation for calcium
  carbonate that is used to calculate antiscalant
  dosages. In reverse osmosis and nanofiltration
  systems, even a very thin layer of calcium
  carbonate scale will impact performance. Most
  antiscalant projection software rely on the
  Langelier Saturation Index (LSI) or the Calcium
  Carbonate Precipitation Potential (CCPP) which
  quantify how much scale will form. That quantity
  of scale could form in seconds or over a period
  of several days, and this has made these two
  methods

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• inadequate for reliably calculating the most
  optimal dosage of RO/NF antiscalant. The key is
  to determine whether formation is slow enough to
  be controllable by antiscalant, and if it is,
  then an exact dosage can be determined to
  redissolved crystal nuclei at a faster rate than
  they form.
• Antiscalant Precipitation Index (API) This index
  is the first of its kind in determining the
  limitations of various antiscalants in a membrane
  system. All scale inhibitors have the tendency
  to form calcium or magnesium scales. This applies
  to phosphonate, acrylate, and even green
  antiscalants. AWC has also identified complex
  calcium-carbonate-antiscalant salts that form
  under certain conditions. The API calculates the
  solubility of antiscalants based on the amount of
  calcium in the water, alkalinity, pH, ionic
  strength, ion complexes, and temperature. It
  accounts for the different solubilities of
  different antiscalant salts, and accurately
  predicts whether a given dosage will result in
  antiscalant salt precipitation. Those who have
  been in the membrane industry long enough will
  recognize cases where scaling has occurred even
  when the calcium carbonate saturation was
  relatively low. This occurs because of
  precipitation of calcium-antiscalant salts when
  the active inhibitor is lost, mineral scaling
  will form. The API allows the user to predict the
  likelihood of this type of scaling and
  accordingly make adjustments while still in the
  design phase.
• Malki Phosphate Index (MPI) This is the only
  calcium phosphate saturation index that accounts
  for pH, temperature, ion complexes and ionic
  strength. Because calcium phosphate has such low
  solubility, its saturation can be directly
  correlated to its rate of formation. The MPI
  accurately determines whether calcium phosphate
  scaling will occur, and allows for antiscalant
  selection and dosage calculation for its
  inhibition.
• Malki Silica Index (MSI) Silica formation can be
  slow enough so that a silica saturated solution
  may not precipitate until well after it has left
  the membrane system. The rate of formation is
  therefore essential in predicting how silica will
  impact the membrane systems operation. Silica
  polymerizes into colloidal particles that grow
  and/or agglomerate to form silica scale. Certain
  cations such as calcium and magnesium can make
  silica less soluble and increase its rate of
  polymerization. Silica is more soluble at higher
  pH, but AWC studies have shown that higher pH
  also increases the rate of polymerization at high
  ionic strength. Silica solubility increases at
  higher temperature, but paradoxically, its rate
  of polymerization is also faster with increasing
  temperature. The MSI accounts for all these
  competing mechanisms, and provides the most
  accurate prediction tool in the industry. Most
  antiscalant projection software calculate maximum
  recovery by assuming that a concentration of up
  to 300 ppm silica can be controlled by
  antiscalants this overly simplistic approach is
  never reliable. By contrast, the MSI uses a
  highly sophisticated algorithm to account for
  all the thermodynamic and kinetic properties of
  silica so as to predict the behavior of silica
  in the system. The MSI can reliably estimate the
• amount of time that silica scaling will cause a
  10 15 decline in permeability this is
  extremely useful when performing cost analysis,
  allowing the designer to compare the cost of
  cleaning vs the cost of brine disposal while
  operating at a lower recovery.
• What is the Chemical Speciation function in
  PROTON?

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• PROTON speciates weak acids, weak bases, metal
  hydroxides, and ion complexes based on pH, ionic
  strength, oxidation state, and temperature. This
  allows the user to determine the number of
  charges that the compounds will carry under any
  given set of conditions. This is essential for
  predicting both scale formation and front end
  membrane fouling by metal hydroxides. The
  speciation function also allows the user to see
  changes in the charges of any species with
  changes in temperature or pH in real time a
  function that is extremely useful in optimizing
  pH for upstream coagulation. Finally, it allows
  the user to design for post treatment
  degasification based on carbon dioxide, ammonia,
  and/or hydrogen sulfide in the permeate.
• Why is PROTON only available as a cloud based
  software? PROTON is cloud based for three
  primary reasons
• It can be accessible from any computer, tablet or
  smartphone that has an internet connection.
• Updates and improvements to the software can be
  performed seamlessly without the need for the
  user to download an update.
• Cloud based software can be constantly monitored
  for functionality, and eliminates issues
  associated with computer operating systems that
  are constantly changing from one year to the
  next.
• How can I be assured that information that I
  enter intoPROTON will remain confidential, and
  not violate any non-disclosure agreements I may
  have?
• PROTON is based on a highly secure server with
  multiple layers of security. Furthermore, it
  does not allow any user to sign in without
  agreeing to the terms and conditions of use,
  which include a non-disclosure agreement (NDA)
  between the user and American Water Chemicals,
  Inc. This NDA provides the user with assurance
  that American Water Chemicals will be bound by
  confidentiality and will not share any of the
  users information without explicit permission
  from the user.
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