Our Thorough Explanation of Ion Exchange
First discovered in 1850 during a scientific research project, ion exchange is now a water treatment method designed to soften hard water. It all began when Thomas and Way researched to see if there was such a thing as ion exchange.
Thomas and Way conducted their research by passing ammonium sulfate through soil. After passing through the soil, they found calcium sulfate instead of the ammonium sulfate they’d started with. But they didn’t realize the significance of what they’d discovered for several years until they realized the reaction was reversible.
Ultimately, what began as an experiment became an effective solution for treating water.
So, we know that ion exchange is a form of water treatment and that it treats hard water, but what exactly is it? How does it work? How much does it cost? And how good is it for your health?
Today’s blog contains our thorough explanation of ion exchange so that you can learn everything you need to know. By the end of this blog, you should have a good idea of whether you want to use ion exchange water treatment for your facility’s water.
What Are Ions?
Ions are atoms or molecules that have a net electrical charge. The net electrical charge of an ion changes when it loses or gains electrons. Positively charged ions are called cations, while negatively charged ions are anions.
What Is Ion Exchange?
Ion exchange is a chemical process that eliminates dissolved ions in water and wastewater. Nitrate, fluoride, sulfate, and arsenic are examples of the kinds of dissolved ions that ion exchange can remove.
How exactly is this done?
Those unwanted ions are exchanged with other ions that contain similar charges. As those ions are attracted to each other, the dissolved ions contaminating the water are removed and replaced by better ions.
Removing Ion Contaminants
The exchange of ions to remove unwanted ions happens when a solid, like a resin or a zeolite, connects with a liquid, like water. After the more desirable ions replace the unwanted ions, the desirable ones are loaded onto the resin material. The resins are used to remove more ionic contaminants from the water.
When the cations (positively charged ions) make contact with the ion exchange resin, they attach themselves to the resin and are exchanged with the ions living on the resin surface. Sodium is usually the ion on the resin surface.
When the anions (negatively charged ions) touch the ion exchange resin, they’re exchanged with the negatively charged ions living on the resin surface. Chloride is the ion here.
During this process, multiple ion contaminants are removed. Ion exchange is beneficial if you want to remove a pollutant with a low concentration, like boron.
What Are Ion Exchange Resins?
So, what exactly is an ion exchange resin? Each resin is made of organic solvents and tiny, microporous beads that can’t be dissolved in water. Polystyrene and polyacrylate are the most popular beads used for ion exchange resin. Each bead’s diameter is approximately 0.3 to 1.3mm. The beads are half water.
Recharging Resins
Resins are critical to the ion exchange process, but they won’t last forever. Eventually, the resin will get “full” from too many ions attaching to it. To continue their role in the exchange process, resins must be recharged.
You can recharge resins with sodium chloride, hydrochloric acid, sulfuric acid, or sodium hydroxide. The chloride, acid, or hydroxide you use is “spent regenerant.” The spent regenerate contains every removed ion, any extra regenerate ions, and a high level of total dissolved solids.
You can treat the regenerant in a municipal wastewater facility, but you’ll need to monitor the discharges.
Resin recharging is essential. If the resin doesn’t work properly because it’s too full, you’ll deal with issues like mineral scaling, surface clogging, and resin fouling. These issues will prevent the full process of ion exchange and leave you with contaminated water.
The Operation, Maintenance, and Cost
Ion exchange treatment does require maintaining your equipment. But there’s no blanket maintenance method since the type of softener varies. Because of this, you’ll need to monitor your ion exchange system to ensure the unit properly regenerates. One aspect of this involves ensuring that the resin bed has adequate backwashing.
If you have issues with your system that basic maintenance doesn’t fix, you may need to call in professional help.
The cost of your ion exchange system will significantly vary. It depends on how large your facility is and how much water you use, as well as pretreatment and discharge requirements.
Health Aspects
Are there health concerns you need to keep in mind? If so, there are a couple of things you should know.
First, people with sodium restrictions in their diets should be cautious since sodium is one of the ions that replace contaminants. You should consult with your physician on whether ion exchange treated water is healthy for you. On the other hand, if you have a sodium deficiency, ion exchange treated water might be just what you need.
Second, you should avoid watering plants with soft water if you have plants. The higher sodium concentration is bad for plants, lawns, and gardens. Watering them with soft water once or twice isn’t the end of the world, but repeated watering could injure or damage the plants.
Is Ion Exchange Right For You?
Ion exchange primarily treats groundwater nitrates and removes arsenic, metalloids, or metals. If that’s what you need, ion exchange might be exactly what you’re looking for.
J.Mark Systems
Are you considering ion exchange for your water treatment? J.Mark Systems is your industrial water treatment solution. We’ve simplified the process to make it as easy as possible.
We offer premier performance, eco-friendly systems, turnkey solutions, and in-house financing for ion exchange, wastewater, reverse osmosis, and other treatment technologies.
Are you ready to get started with ion exchange treatment for your industrial water supply? Maybe you have questions about the process? J.Mark Systems is here to answer your questions! Contact us today to learn more.