WaterTechOnline.com, From Volume 31, Issue 2 - February 2008
Mineral scale formation on the surfaces of pipes and other water system components has for many years been one of the major target markets for professional water treatment. Scale is at least a nuisance in a home water system, and its presence in commercial and industrial applications costs into the billions of dollars.
In one study cited by the Water Quality Association (WQA), gas water heaters operating on hard water (the principal source of mineral scale) consumed almost 30 percent more energy than gas water heaters operating on soft water. The added hard-water cost for electric water heaters was not far behind about 22 percent.*
In commercial and industrial boilers, cooling systems and process applications, scale build-up can literally shut down such systems or, at the very least, boost their energy consumption requirements dramatically.
Scale buildup restricts or blocks water flow and, in heating/cooling systems, forms an insulating layer that reduces the heat-transferring capability of boiler tubes, cooling tower elements and the like.
Many scale problems occur when calcium (Ca) and magnesium (Mg) compounds dissolve in water and the ions of those metals recombine and form far less soluble carbonate compounds. Those less-soluble compounds (sidebar, page 23) precipitate out of the water and attach themselves to pipe walls and water system hardware. Iron and silica in water are among other sources of scale.
Water treatment dealers faced with scale issues have a number of alternatives, and it turns out that some newer scale-reduction technologies are likely to move increasingly to the center stage of residential, commercial and industrial point-of-use/point-of-entry (POU/POE) treatment.