Water is a Polar Molecule
Hydrogen Bonds in Water
Scale Control Mechanism
Enhanced Colloidal Charge
Operating Principles
Treatment Effects Last
Current Source Generators

Calcium carbonate (CaCo3) is the primary constituent of scale in water systems. Calcium and carbonate ions enter the water as parts of other molecules that are dissolved in the water. The ions join to form calcium carbonate when they precipitate out of solution at the surfaces of the equipment.

The calcium and carbonate ions are "hydrated" when they are dissolved in the water. This means the ions are surrounded by water molecules that are attracted to the ions by the electrical charge. When ionic compounds such as salt (sodium chloride) or calcium carbonate enter water, the polar water molecules seek to hydrate the ions from the molecules, because the electrostatic attraction potential of the water molecules is very high. The water molecules greatly reduce the attraction of the ions in the ionic compound molecules, so that the ions only interact weakly with each other and do not aggregate into crystals.

A substance will dissolve only if the attractions between its ionic charge centers, and the water molecules are sufficient to overcome the attractions between its own ionic charge centers. As water dissolves a substance, water molecules will surround the ions and form electrostatic bonds with the dissolving ions. As these bonds between water molecules and dissolving ions form, energy is released (known as the heat of hydration). When this hydration heat becomes larger than the bonding energy between the ions on the dissolving substance, the ion will dissolve into the water solution.

Heats of hydration are typically much smaller than the bonding energy between the positive and negative ions of an ionic compound. Therefore, each ion of a solid unit must be surrounded by many water molecules before it can be solvated. In other words, large aggregates of water tied up with hydrogen bonds cannot effectively dissolve solutes, whereas separate water molecules can.

The main culprit in most scale problems is the super-saturated solution. There is so much scale-causing mineral in the solution that ions are only partially hydrated. The scale-causing minerals such as calcium and magnesium ions are unstable and "barely hanging in water" in a super saturated solution. If the scale-causing minerals are left untreated and conditions such as pH, temperature, and pressure change in a fluid system, the solubility of scale-causing minerals may decrease. (In cooling towers, condensers, boilers, and other equipment, changes in temperature are integral parts of their operation.)

The electrostatic attraction between the dissolved mineral ions and metal surface area charge makes these minerals stick to the surfaces. This is why the scales are unavoidable without some active scale prevention measures.

The induced molecular agitation in the Triangular Wave electronic deposit control system causes the unstable mineral ions to collide with each other and precipitate. Impurities in the water such as alumina or silica provide initial nucleation sites for further precipitation of adjacent mineral ions.

A snow ball effect starts, resulting in the growth of many crystals, each consisting of numerous mineral ions. This enables crystal salts to become large in size and float with water; thus they do not stick to the metal surfaces, because the crystals do not have the charges at the surface anymore.

As the byproduct of the above mentioned precipitation and snowball effect of mineral particles, freed water molecules become available to dissolve existing scales.

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