PROTON®: The World’s Most Advanced Reverse Osmosis Antiscalant Software
PROTON® is our cloud-based water treatment and chemical dosing software, built specifically for reverse osmosis (RO) and nanofiltration (NF) system designers. It accurately calculates antiscalant dosages, models scale saturation across more than 50 scale types, predicts salt and contamination rejection, and provides real-time system design tools that no other antiscalant software on the market can match.
What sets it apart is how it works under the hood. Where standard antiscalant software leans on simplified formulas and fixed assumptions, PROTON® bases every calculation on thermodynamic data drawn from peer-reviewed scientific research. Membrane flux, ion activity, ion complexes, real-world operating conditions at every stage of your system – it’s all accounted for. That translates into dosing recommendations you can actually trust, accessible from any device, anywhere.
What is PROTON® and what does it do?
PROTON® is a cloud-based water chemical dosing software and RO system design tool developed by American Water Chemicals® (AWC®). Water treatment engineers and membrane system designers use it to calculate antiscalant dosages, predict scale formation, model membrane performance, and optimize system recovery, across both reverse osmosis and nanofiltration systems.
In practice, that means being able to compare required feed pressure and permeate water quality for different membranes side by side, and to see in real time how changes in pH, temperature, or recovery affect pressure, flux, and water quality. Switch membrane type mid-design and the numbers update instantly.
It’s also the first antiscalant software to account for membrane flux rates at each individual stage of a system, and why that matters is explained in detail below.
How does PROTON® calculate water chemical dosing?
Most water chemical dosing software works from simplified formulas, applying fixed salt rejection rates across a system and treating every stage as if it behaves the same. It’s a shortcut that introduces error at a point where accuracy matters most.
PROTON® takes a different approach entirely. Every dosing calculation is grounded in thermodynamic data sourced from peer-reviewed scientific research. Temperature, ion activity, and ion complexes are factored into every single calculation – over 130 ion complexes in total, across the full RO operating range of pH 1 to 11.
PROTON® is the first antiscalant software that accounts for how salt passage actually changes with membrane flux, at each individual stage of a system. Salt concentration, which is what drives scale formation, isn’t uniform across a system. It shifts from stage to stage depending on flux. Ignore that, and your dosing calculations are working from the wrong numbers.
PROTON® doesn’t ignore this mechanism. The result is optimum scale inhibitor dosages for NF, RO, and NF/RO hybrid systems, with a level of precision no other water treatment software comes close to.
Why is PROTON®’s approach to salt rejection more accurate than other antiscalant software?
Because 100% salt rejection doesn’t exist in the real world, and building a system design around that assumption means your scaling predictions and antiscalant dosing are based on incorrect numbers.
Every RO and NF membrane lets a small amount of salt through. Moreover, the amount that passes through isn’t fixed, it changes depending on how fast water is being pushed through the membrane (known as flux). Push harder, more gets through. It also varies from one stage to the next within the same system.
Most antiscalant software either ignores this entirely, or lets users type in a rejection rate and applies it as a flat figure across every stage. Both approaches miss what’s actually happening inside the membrane.
PROTON® accounts for how salt passage shifts with flux at each step. Since salt concentration is what drives scale formation, getting this right has a direct impact on everything downstream: more accurate scaling predictions, dosages that reflect reality, less risk of scale buildup, and no money spent on chemicals you don’t need.
What makes PROTON® different from other antiscalant software?
Beyond salt rejection, PROTON® sets a new standard across every aspect of antiscalant software, from system design to scale prediction accuracy.
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 manufacturer’s 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 software capable of modelling Desalitech’s 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, PROTON®’s 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.
How can PROTON® help with RO 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 g that help with design of pretreatment coagulation and post-treatment degasification (see below: Chemical Speciation).
What are the things only PROTON® can do?
Some of the capabilities below might seem like technical footnotes, but they are not. Each one addresses a real gap in how other antiscalant software handles complex or edge-case systems, and in the field, edge cases are common.
PROTON® is the only antiscalant software that:
- Accounts for membrane flux and salt passage at each individual stage of a system, rather than applying a flat rejection factor across the board.
- Models Desalitech’s Closed Circuit Reverse Osmosis (CCRO) technology. No other antiscalant software can do this.
- Predicts arsenic rejection as a function of pH, temperature, and ionic strength.
- Calculates scaling potential for over 50 different scales, using thermodynamic data from peer-reviewed research rather than canned formulas that break down outside a narrow pH or TDS range.
- Accounts for over 130 ion complexes, enabling accurate modelling across the full RO operating range of pH 1–11.
- Includes five proprietary indices developed by AWC® that aren’t available in any other antiscalant software: the Calcium Carbonate Nucleation Index (CCNI), the Antiscalant Precipitation Index (API), the Silica Kinetics Index (SKI), the CaSiO₃ Index, and the CaSi₂O₄ Index.
- Identifies the risk of antiscalant precipitation itself, predicting whether a given dosage will form calcium or magnesium antiscalant salts, a failure mode that goes undetected in all other dosing software.
- Is the first membrane antiscalant software to incorporate the lithium ion, supporting NF/RO system design for lithium mining applications.
What are PROTON®’s five proprietary scaling indices?
PROTON® has introduced five powerful new indices:
1. 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.
2. 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.
3. Silica Kinetics Index (SKI)
The SKI is the only index that considers both the thermodynamic and kinetic properties of silica to predict membrane scaling. The rate of silica scale formation is essential in predicting how it will impact the membrane system’s operation.
In theory, silica solubility increases at higher pH, but certain cations, such as calcium and magnesium, can make silica less soluble by neutralizing the repulsive charges. This increases the rate of polymerization, resulting in faster silica scale formation. Ionic strength also plays a significant role, with dramatic increases in the rate of silica polymerization under high ionic strength conditions. Silica is most soluble at higher temperature, but paradoxically, its rate of polymerization is also faster with increasing temperature. The SPKI accounts for all these competing mechanisms, allowing the user to determine the highest recovery at which silica scaling can be inhibited.
4. CaSiO3 Index
This index predicts formation of calcium silicate at high pH conditions. AWC® experimental work has shown that calcium silicate formation can trigger heavy silica scaling, meaning that its inhibition is essential to silica scale control. This index is calculated based on thermodynamic properties that consider pH, temperature, ion complexes and ion activity, but additionally corrects for temperature based on kinetics of nucleation. By predicting the conditions at which CaSiO3 will nucleate, maximum recovery and maximum operating pH can better be predicted for any water quality.
5. CaSi2O4 Index
Where the CaSiO₃ Index addresses high pH conditions, the CaSi₂O₄ Index predicts formation of calcium silicate at neutral pH. Experimental research conducted by AWC® has demonstrated that any nucleation of CaSi2O4 crystals can trigger severe silica scaling, and its inhibition is therefore essential to silica scale control. The calculation draws on thermodynamic properties (pH, temperature, ion complexes, and ion activity) with an additional correction for temperature based on nucleation kinetics. Knowing the conditions at which CaSi₂O₄ will nucleate allows for more accurate prediction of maximum recovery and maximum operating pH across any water quality.
What is the Chemical Speciation function in PROTON®?
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.
Does PROTON® support lithium mining membrane applications?
Yes, and it’s the first membrane antiscalant software to do so. As demand for lithium grows alongside the rise of battery-powered devices and electric vehicles, AWC® has added the lithium ion to PROTON® to support NF/RO system design in lithium mining applications.
PROTON® accounts for:
- The impact of lithium on osmotic pressure
- Lithium’s contribution to ionic strength
- Salt passage of the lithium ion under variable conditions
- Indirect impacts of lithium ion concentration on mineral scale formation in brine concentrator systems
This allows users to maximize NF/RO recovery and significantly reduce the cost of pretreatment and evaporation/crystallisation processes, making PROTON® one of the few tools equipped to handle the specific challenges of lithium brine treatment and direct lithium extraction at membrane level.
Is PROTON® available as a cloud-based app?
Yes. PROTON® is a fully cloud-based reverse osmosis software application; no installation, no downloads, no version conflicts. It runs in any browser, on any device, which makes it one of the more practical RO and NF apps available to engineers working across multiple sites or client projects.
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 I enter into PROTON® will remain confidential, and not violate any NDA’s 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 user’s information without explicit permission from the user.
Why is AWC’s 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 does PROTON® compare to standard antiscalant software?
Most antiscalant software is a dosing calculator built on simplified formulas. PROTON® is a different kind of tool. Here’s where the differences show up in practice:
Salt rejection modelling: Standard software often assumes 100% salt rejection, or at best applies a flat rejection factor across the whole system. PROTON® accounts for how salt passage actually changes with membrane flux at each individual stage – because it does change, and ignoring that produces the wrong numbers.
Scale prediction accuracy: Many programs use canned formulas that break down outside a certain pH or TDS range. PROTON® uses thermodynamic data from peer-reviewed research, accounts for over 130 ion complexes, and works accurately across the full RO operating range of pH 1–11.
Number of scales modelled: Most software covers the common scales. PROTON® calculates scaling potential for over 50 different scale types.
Antiscalant precipitation: This one catches people off guard. The antiscalant itself can precipitate as a calcium or magnesium salt under certain conditions, and when it does, you lose your active inhibitor and mineral scaling follows. No other antiscalant software identifies this risk. PROTON®’s Antiscalant Precipitation Index (API) flags it before it becomes a problem.
System design: Most dosing software stops at dosing. PROTON® is also a full RO system design tool that allows users to compare membrane types, pressure requirements, and permeate water quality side by side under identical conditions.
CCRO modelling: PROTON® is the only antiscalant software capable of modelling Closed Circuit Reverse Osmosis (CCRO) technology.
Arsenic rejection: PROTON® is the only software that predicts arsenic rejection as a function of pH, temperature, and ionic strength.
Lithium mining applications: PROTON® is the first membrane antiscalant software to incorporate the lithium ion, accounting for its impact on osmotic pressure, ionic strength, and salt passage, enabling accurate NF/RO system design for lithium brine treatment and direct lithium extraction processes.