Acid attack is mainly caused by acid spillage, or acid in the form of smoke, rain or exhausting gasses.
Concrete is quite vulnerable to acid exposure, because of its alkaline nature. The components of the cement paste break down during contact with acids.
Acids such as nitric acid, hydrochloric acid and acetic acid are very aggressive as their calcium salts are readily soluble and removed from the attack front. Other acids such as phosphoric acid and humic acid are less harmful as their calcium salt, due to their low solubility, inhibit the attack by blocking the pathways within the concrete such as interconnected cracks, voids and porosity. Sulphuric acid is very damaging to concrete as it combines an acid attack and a sulphate attack.
The most common acid attack is by acid sulphuric which is available in sewage canals, wastewater treatment plants and industrial areas. It deteriorates concrete structures by reacting with cement hydrates.
H2SO4 + Ca(OH)2 Ca(SO)4 + 2H2O
Sulphuric acid attack causes formation of gypsum in the regions close to the exposed surface, and this causes disintegration and mechanical stresses which lead to spalling and exposure of the fresh interior surface and this cycle repeats itself over and over again.
What we offer, at GESS, is a complete solution for Acid-resistant Concrete. In this process, we removed the damaged concrete, laid the new acid resistant concrete and then few layers of coatings which also need to be resistant to acids.
We do offer this package, as we have the experience of working with laboratories and chemists.