The most effective descaling is accomplished by circulation. 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 and sludge, then pre-cleaning with Seaclean Plus or Enviroclean.
Depending on the extent of scaling, use a solution of 2.5-10% Descalex. The solution will have a red colour which disappear when the solution is neutralised. Whenever possible, the solution should be heated to 60°C.
Neutralised solutions can be reactivated by adding more Descalex until the red colour reappears. This should not be done more than twice.
Descalex should not be used on aluminium, zinc, tin or galvanised surfaces.
After use of Descalex a 0.5% solution of Alkalinity Control in fresh water should be used for neutralisation.
Descaling of Boilers, Descaling of Diesel Engine Cooling Water Systems, Condensers, Evaporators, Calorifiers, Heat Exchangers:
See Unitor’s Unitor’s Water Treatment Handbook.
Unitor has developed a 210 litres capacity cleaning unit designed 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. 737189
Notes regarding safety in descaling operations:
Descalex 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.