Fighting of Silicates – ANTISIL

Um Silikatablagerungen zu entfernen, kann nur eine Säure verwendet, nämlich Flußsäure; sie enthält spezielle Korrosionsinhibitoren, welche die Aufgabe haben, die metallischen Werkstoffe vor einem Säureangriff zu schützen. Es bildet sich dabei selektiv ein monomolekularer Schutzfilm auf der Metalloberfläche, ohne dass dadurch die Auflösung des Belages durch die Säuren behindert wird.

ANTISIL – Dissolving agent for the chemical extraction of silica based deposits – contains hydrfluoric acid.

The Application

ANTISIL can be mixed with water in any ratio, but it is advisable not to exceed a dilution ratio of 1 : 20, because otherwise losses caused by water hardness get too high and dissolving time gets too long.

With limescale ANTISIL forms an insoluble calcium fluoride (fluorite) which blocks further dissolving of silica. Therefore, in carrying out a boiler mineral scale removal procedure, the – almost always exsiting – calcium carbonate has to be dissolved away with KALZITIN first.

ANTISIL is usually applied cold and may be filled only into cooled down boilers. ANTISIL solutions shall be recycled little, which means, that reaction of ANTISIL with the mineral deposit shall take place as calmly as possible.

Calculation of necessary amount:
Having a silicate deposit with an average specific weight of 2 a need of 19 kg ANTISIL for 1 dm3 of silicate mineral results (that is 1 mm deposit thickness per 1 m2 mineral covered surface).

After having finished the mineral scale removing procedure, after max. 48 hours, the system is emptied, it is flushed with water thoroughly and after a possible intermediate flushing with SULFATEX-A (2 to 10 % (bw) solution) the system is treated with TRINEUTRAL.
The treatment with SULFATEX-A depends on film rust formation und may last from 1 to 24 hours.

The used ANTISIL solution is hazardous waste and has to be disposed of / treated by a licensed hazardous waste disposal contractor.