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next-ScaleStop Scale Prevention

Next Filtration offers next-ScaleStop, a scale-preventing water treatment that uses template-assisted crystallization (TAC) to effectively prevent scale without an electric draw or ion replacement… Read more
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Tristan Roberts
Editorial Director

Next Filtration offers next-ScaleStop, a scale-preventing water treatment that uses template-assisted crystallization (TAC) to effectively prevent scale without an electric draw or ion replacement. The next-ScaleStop process media, which should be replaced every three years, is calcium-coated beads of polystyrene pockmarked with small nucleation sites (the "template" in TAC). Calcium and bicarbonate ions will crystallize at the nucleation sites, forming "soft scale" which will drift through plumbing without accumulating or interfering with energy transfer. The next-ScaleStop is warranted for 10 years, and can handle water with a maximum hardness of 75 grains and temperatures ranging from 41°F–140°F. Single-unit systems can handle 1–75 gpm, while commercial systems can handle up to 900 gpm.

Water hardness refers to the concentration of calcium and magnesium cations. These positively charged ions dissolve in water as it percolates through alkaline soils or bedrock. Hardness is commonly measured either by the concentration of calcium and magnesium ions in the water or by the grains per gallon (gpg) of calcium carbonate dissolved in water. Hard water is closely linked with scale, in which calcium or magnesium carbonate crystallizes on the interior surface of pipes. Scale reduces the efficiency of heat-transfer equipment such as hot water heaters and is expensive and time-consuming to remove.

Water softeners typically work by replacing calcium and magnesium ions with sodium ions, which don’t form scale. Ion exchange water softeners operate with a slight, though continuous, electric draw, and require significant backwashing of sodium ions into the waste stream. Sodium backwashing is particularly problematic in landscape and agricultural settings.

An alternative to water softening is scale prevention without ion replacement. Template Assisted Crystallization (TAC), a relatively new technology, requires no power, and does not replace the positively charged ions with salt, as is common in other products.

TAC systems use tanks or cartridges filled with extremely small, negatively charged beads of polystyrene that are coated with calcium and pockmarked with small indentations, or nucleation sites (the “template” in TAC). When water passes over the beads, the calcium ions react with bicarbonate at the templates, forming calcium carbonate (scale) crystals. These scale crystals break off and float through plumbing colloidally suspended, meaning they wont attach to pipes and interfere with heat transfer.

Although the water treatment market is filled with unproven and questionable technologies, TAC systems have been shown to reduce scale buildup without environmental drawbacks such as electricity use or sodium backwashing. For this reason, GreenSpec lists TAC systems over water softening systems.

For more information, read Template-Assisted Crystallization: Scale Prevention Without Salt.

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