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Water Hardness & Limescale

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Water Hardness & Limescale Water Hardness & Limescale Corrosion Scale "Slight corrosion of iron promotes the precipitation of calcium carbonate (Lime-scale), 2+ since the Fe ions enable the nucleation of CaCO3 at low super-saturations" E.REVAULT, J.BARON, J.LÃ DION, Influence des ions Fe2+ sur le pouvoir entartrant de l'eau. Lime-scale (Hard water) When rain falls through the atmosphere, it takes into solution a certain amount of carbon dioxide making it slightly acidic. This acidity together with the fact that pure water such as rain water is a good solvent causes substances in the ground such as lime stone and chalk to be dissolved. They react with the acidity of the carbonic acid H2CO3 to form soluble salts. These salts exist in the main as either relatively insoluble carbonates or quite soluble bicarbonates of calcium and magnesium. Carbonates are said to be substances which cause "permanent" hardness and bicarbonates cause "temporary hardness". The latter cause most of the problems associated with hard water since the application of heat causes them to break down according to the following equation causing scale. Calcium Bicarbonate plus heat gives Calcium carbonate plus water plus carbon dioxide. Ca (HCO3)2 + HEAT CaCO3 + H2O + CO2 This reverses the original reaction between carbonic acid and the calcium carbonate. The insoluble calcium carbonate is deposited upon heating surfaces and pipes as a result. In the main, chemical methods have been used to combat the expensive and inconvenient problems, which arise as a result of using hard water. Water softeners which use salt to regenerate special resins, which remove calcium ions from water are now less environmentally acceptable, in some countries they have been banned due to the contamination of ground water which contains large amounts of salt effluent from water softeners. Salt-based water softeners do not prevent corrosion unlike the Scalebuster . This is why Physical Water Conditioners are a better choice to reduce the effects of scale on systems than salt-based water softeners. However, unlike certain other types of physical water conditioners the Scalebuster can actually reduce and inhibit corrosion. Scalebuster , through a unique combination of cavitation, dielectric charge and a large surface of zinc anode, enables the premature precipitation of calcium carbonate into the water stream by breaking down a significant proportion of the bicarbonates. These particles act as nuclei for the growth of further scale as they pass through the system. The application of heat causes the scale particles to grow in size as they pass harmlessly through the water system, see the benefit of creating large particles. The removal of some of the dissolved substances from the water causes the water to become less saturated (saturation is the limit of solution of a substance in a given solvent). This allows this less saturated water to commence to dissolve old scale deposits from the walls of pipes and heating appliances. Over a period of time, all old deposits can be flushed from a system. Scale and the environment Scalebuster must be the most environmentally sound method to combat hard water and corrosion scale since it uses no power or chemicals and requires no maintenance. It uses the kinetic energy of a moving stream of water through pipe-work to perform its task effortlessly over a very long time. It has been designed using serious methods of analysis including Laser Particle Analysis, which measures the size and distribution of particles passing through a water supply. The environment is an issue that must be addressed by all of us that are in a position to effect a change. In the future we will not be able to ignore the environmental issues that challenge us today! .
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