The most effective descaling is accomplished by circulation for large systems or components. In the case of small components, the soak method in an immersion bath can be used.
If the equipment to be cleaned is contaminated by oil, grease, sludge or carbonised oil, then pre-cleaning with Seaclean Plus or Enviroclean is necessary.
Descaling Liquid should alway be used in plastic bucket. Acid should always be added to water, and never the reverse.
Descaling Liquid should be mixed with fresh water to form a solution of 10-30%, depending on the extent of scaling. After using Descaling Liquid it is essential to thoroughly rinse all metal surfaces at least once with a 0.5% solution of Alkalinity Control in fresh water. This solution should be circulated for 2-4 hours or until an acceptable pH value is obtained. This will neutralize any remaining acidity and passivate steel surfaces.
Descaling Liquid should not be used on aluminium, zinc, tin, or any galvanised surfaces for which a special grade cleaner should be used.
Unitor has developed a 210 litres capacity cleaning unit designet among other for use with chemical acid solutions for cleaning boilers, calorifiers, heat exchangers and other types of equipment where rust and scale form.
Chemical Cleaning Unit: Product no. 664 737189
Descaling Boilers, Condensers, Evaporators, Calorifiers and Heat exchangers:
See Unitor Unitor Water Treatment Handbook.
Notes regarding safety in descaling operations:
Descaling liquid contains strong acids. Handle with care and pay special attention to Material Safety Data Sheet and / or Product Label. Use personal protection equipment as recommended.
Reaction products from acid components in decaling products may include gasses like carbon dioxide and hydrogen. Formation of hydrogen gas can be monitored with gas detection equipment on the vents. To avoid suffocation and potentially explosive atmosphere, gasses should be removed safely by purging system with water after draining the cleaning solution. Vent of system during descaling operations must be provided for same reason. Always use gas detection equipment to check that the atmosphere is safe before entering confined spaces for inspection after descaling operations. When circulating the descaling solution, always circulate with inlet at the bottom to avoid air pockets and potential entrapment of gaseous reaction products.