- Country of manufactureUkraine
Protection materials from GAS corrosion of concrete, repair materials for concrete, construction chemistry, means of protection of concrete surfaces from corrosion
Protection materials from GAS corrosion of concrete, repair materials for concrete, construction chemistry
Short description of problem of gas corrosion and perspective of its decision.
The problem of gas corrosion consists in drawing protective polymer coatings, for example, of epoxides, urethanes, polyurethane, etc. for reduction of penetration of hydrogen sulfide into concrete by means of protective layer. All concept is based on diffusion minimization, and the main argument is that at the same time there is hydrogen sulfide penetration reduction, in concrete less sulphuric acid because of bacteriological process is formed, reducing these probability of destruction of concrete. Theoretically this argument is reasonable and correct.
The problem is that absolutely few from those people who make formulas of such high density coverings ever were in sewer systems. In practice situation slightly another. Concrete surface of sewer systems uneven, crude and contaminated. It is difficult to clear it and it is impossible to keep its all the time dry. It is also almost impossible to make layer ideal without microopenings and cracks. Water gets through these coating defects and capillary tension on surface of joints razshcheplyat polymer coating. It occurs everywhere where concrete is covered with polymer in the continuous wet environment. In sewer systems one more problem - availability of hydrogen sulfide takes place. In our opinion, approach to solution by means of use of coverings on polymeric basis is doomed to failure, and to that there is set of certificates when such systems do not work.
One more problem, is that standards are based on resistance of protective coatings, approximately, for 10% of sulphuric acid. This type of testing is absolutely inappropriate as low concentration of N2B does not represent such sharp acidic environment. The sulphuric acid formed by bacteria in concrete - here that is the reason of its destruction. Thus, if the polymer coating is not effective because of the defects (what cannot be avoided), then corrosion "under" protective layer continues. Therefore resistance of protection material to chemical influence in itself is almost insignificant.
The decision for successful recovery of concrete use of the repair materials having the following characteristics is key:
1) Good coupling with surface of the destroyed concrete of sewer system
2) Sufficient thickness + insignificant permeability for reduction of diffusion of hydrogen sulfide through layer
3) Lack of cracks
4) Higher resilience to chemical influence of acid condition in comparison with traditional concrete.
Our materials correspond to these criteria.
We are sure that this decision will be much better than those which are used now.