Water Softener Resin Structure

We sell a lot of water softeners at Aquatell and it's a topic we're especially passionate about. We love talking with customers and helping them to understand what they need, why they need it, and help them to learn enough that they can progress confidently on their softener journey.

Like most topics, water softening seems superficially simple: hard water goes into a softener, and comes out soft. But dig just a little under the surface and you quickly realize that water softening (more accurately called ion exchange) is a topic that is firmly rooted in science: mostly chemistry and physics. Learning the nuances of water softener engineering, manufacturing application and troubleshooting is all about understanding the underlying science.

Much of what happens in a water softener happens because of the water softener resin and happens at the microscopic level. In a recent conversation with one of our resin suppliers, I was provided with some really fascinating images of the microscopic structure of water softener resin. Being able to visualize the structure of the resin really helps to provide a visual understanding of the underlying science. Check out these super cool images and our descriptions below.

Water Softener Resin Bead at 100X Magnification

At this level of magnification you can see the very spherical shape of the bead and you can see the size of the bead too. It looks to be about 400 μm (aka microns) in diameter. To put that in perspective, a human hair is about 40 microns in diameter.

What is perhaps most striking about this image (for us at least!) is how the surface structure starts to be revealed at this magnification. A bead that seems perfectly smooth to the naked eye shows a tremendous amount of surface irregularity at 100X. And the surface irregularity makes the viewer wonder about the internal structure of the bead.....

Water Softener Resin Bead at 1000X Magnification

At 1000X magnification we can see that the surface roughness we observed at 100X looks to extend into the depths of the resin bead. In fact, we can see that the resin bead is not an impervious solid at all but a matrix of resin material and empty space!

Where it may have been easy to imagine that ion exchange occurred on the surface of the resin bead only, seeing this image makes it obvious that the vast majority of the surface area of the bead is internal and that the water being treated by the softener actually passes through the resin and not around it!