Stains can be removed from concrete with dry or mechanical methods, or by wet methods using chemical or water.
Common dry methods include sandblasting, flame cleaning and shot blasting, grinding, scabbing, planning and scouring. Steel-wire brushes should be used with care because they can leave metal particles on the surface that later may rust and stain the concrete.
Wet methods involve the application of water or specific chemicals according to the nature of the stain. The chemical treatment either dissolves the staining substance so it can be blotted up from the surface of the concrete or bleaches the staining substance so it will not show.
To remove blood stains, for example, wet the stains with water and cover them with a layer of sodium peroxide powder; let stand for a few minutes, rinse with water and scrub vigorously. Follow with the application of a 5 percent solution of vinegar to neutralize any remaining sodium peroxide.
- Badges
- Science topic
- Similar topics
- Methodology
- Laboratory
- Laboratory Techniques