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How HydroFLOW Can Descale Systems and Equipment

ECMI helps clients descale systems and equipment by implementing HydroFLOW on various facility systems. 

HydroFLOW:

  • Is a chemical-free water treatment solution.

  • Will control and typically descale facility systems. (see descale below)

  • Continues to keep lime scale from forming within facility systems.

  • Keeps equipment operating at peek heat transfer efficiency.

  • Eliminates or reduces costs associated with chemicals used for water treatment and lime scale cleaning.

  • Reduces scheduled cleaning cycles of facility equipment.

HS-38 for domestic descaling

HydroFLOW C Series for commercial descaling

Scale Removal and Descaling

For HydroFLOW to be able to descale a system, certain conditions MUST exist.

System descaling is dependant upon the following conditions:

In a scaling system there are three processes that are at work:

Heterogeneous crystallization, homogeneous crystallization, and scale returning to solution once the solute has become unsaturated.

Heterogeneous crystallization occurs primarily on surfaces that are subject to increasing temperatures. As not all the solute is in contact with the heating surface, supersaturated liquid will be carried away by convection and circulating currents to other surfaces. Scaling on other surfaces will continue until the saturation point is achieved.

Homogeneous crystallization occurs in large vessels containing high volumes of solute, with a relatively small surface area. As the solute is being heated, the solution becomes supersaturated. The surface area is not sufficient to provide all the nucleation necessary. The solute reaches a critical condition. At this point any source of energy, such as turbulence in the solute, will cause homogeneous nucleation. All the material that can precipitate does so at once. Large numbers of small crystals are formed. These crystals have a high surface charge that causes them to adhere to all the surfaces, including cold surfaces. The fine crystals which have adhered to the surfaces will then become the nuclei for heterogeneous crystallization in subsequent heating cycles. 

The third process is the return to solution of the scale deposits. After the solute has become unsaturated due to cooling or pressure change, a quantity of the deposits will be returned to solution. The surface scale that had been formed is not as stable as the crystals that have been formed in suspension, due to the uneven way that nucleation has occurred on the surfaces.

Descaling can occur only if the water in contact with the scaled surface is unsaturated and is able to dissolve the carbonates to form bicarbonates.

The presence of CO2 is necessary for the formation of bicarbonates. The CO2, which is present in solution in the water, comes from two sources, one from the air in contact with the water and the other from the decomposition of bicarbonates due to the heating process.

Descaling of a heat exchanger using HydroFLOW relies on turbulence. This is because the temperature of the water is increasing and would normally only deposit scale. If turbulence is present, the water experiences pressure changes that cause the water to change rapidly from supersaturated to an unsaturated condition. While unsaturated, the water will dissolve the scale on the surfaces, and in the supersaturated condition, the deposits will grow in suspension due to the presence of the clusters generated by the HydroFLOW applied electric field.

In every system containing solute, there is a balance of scale-formation and scale-solution. In a system where the balance favors scale-formation, the system will experience scaling. In a system where the balance favors scale-solution, the system will remain free of scale.

HydroFLOW simply tips the balance in favor of the scale-solution, by providing a large quantity of unsaturated solution that dissolves the existing surface scale. This process is repeated, dissolving surface scale and forming suspended stable crystals. The heterogeneous crystallization is replaced by homogeneous crystallization. However, in this case homogeneous crystallization occurs as soon as the solute becomes supersaturated, due to the presence of a large quantity of clusters generated by HydroFLOW. As a result, the old scale will ultimately completely return to solution and is converted to stable individual crystals. These stable amorphous crystals can be removed by filtration in circulating systems. In open systems they will pass harmlessly out with the flow.


 
 

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