Wednesday, November 27th, 2019 by Mike Ohlinger
For the most part, we have a general idea about how many of our home’s appliances work. Our ovens, refrigerators, washers, dryers, and water heaters all operate under pretty simple principles, even if the mechanics behind them are complicated.
Unless you’re already well-versed in the science of water treatment, trying to explain how the water softener in your basement works can be a little trickier. Questions like “How does adding salt to water make it soft?” or “What is actually inside of that tall tank?” are natural reactions when trying to decode the mysteries of water treatment.
The science behind softening the water that you use every day may be complicated and intricate, but the basic process behind how your water softener works is easier to understand than you might think!
The first step in understanding how your softener works is to recognize the components that make up your system. Your water softener will have two main parts:
The Media Tank: The media tank is the taller and skinnier of the two tanks. It is capped by the control valve and an electronic controller. This serves as the brain of the system, containing all of the programming to make your treatment device provide consistent, soft water as well as the functionality to clean the media inside the tank.
Inside the media tank is an ion-exchange media, either resin beads or zeolite, which removes the minerals that make up hard water.
The Brine Tank: The brine tank is the shorter tank which contains water softener salt. If you think back to your childhood science class, salt is a compound of Sodium and Chloride, or NaCl. This salt, when combined with water, makes a solution called “brine” that is used to clean the resin in the media tank once it has absorbed its capacity of hardness minerals. The two tanks are connected by a tube called a brine line which feeds water between the two during regeneration.
The softening process primarily takes place in your media tank. Raw, hard water enters the tank through the valve at the top, runs through the softening media where the hardness minerals are removed, and then the now softened water flows back out to the fixtures and appliances in your home, free of the damaging components present in hard water.
This process behind how the resin is removing the hardness is called Ion Exchange and it’s where the science behind water treatment really becomes apparent. To imagine how this process works, you’ll need to picture a magnet. As you probably learned in that same science class, opposite polarities (positive and negative) attract each other.
The resin beads or zeolite crystals in your media tank naturally carry a negative charge. When the media in the tank is ready to soften water, the beads or crystals are covered in positively charged sodium ions that stick to media like a magnet.
Hard water contains minerals such as calcium and magnesium which are positively charged like the sodium ions, but are stronger. When the hard water containing these minerals flows over the media, the stronger charged hardness minerals force the sodium ions off and get stuck to the media instead. So, the harmless sodium ions flow out of the tank while the damaging hardness ions are left in the tank, attached to the media. This is how you get soft water!
When the media becomes too full of hardness minerals to capture any more, the system goes into regeneration. This process will typically be set to occur in the middle of the night while your home is not using any water. A normal regeneration process has four steps to it:
1.Brine Tank Fill: The media tank will add softened water to the brine tank, filling it up partially. As the water comes in contact with the salt, it begins to form a saltwater solution called brine. The water will continue to sit in the tank with the salt for a few hours to make a potent solution.
2.Backwash: Raw, hard water enters the top of the tank, runs down through the middle, and then is forced up from the bottom of the tank. This agitates and stirs the media, flushing out any debris to the drain.
3.Brine Draw: After the brine solution is formed, it is drawn into the media tank. The saltwater (or NaCl and H2O) flows past the negatively charged resin beads and causes the positive sodium ions to take back their place on the resin beads or zeolite crystals while the previously attached hardness minerals are flushed to the drain.
4.Rinse: The media tank is given one final rinse to push out any excess salt that may be in the tank.
After the final rinse, the unit is ready to soften water again! The media is fully recharged with sodium ions, ready to repeat the softening process.
WaterCare’s advanced line of softeners and conditioners will continue to soften water and regenerate on their own as long as salt is added regularly to the brine tank. Everything is automated and tailored to your home’s unique water, even the ion exchange process. It works behind the scenes to ensure you have continuously soft water.
With the knowledge of ion exchange in hand, it’s a great time to look even further into the benefits that a water softener or conditioner can have on your home. If you’re interested in taking the leap to fix your home’s problem water, give the WaterCare experts a call today. Your local dealer will test your home’s water, examine the results, and choose a water softener or conditioner specifically tailored for your home!