Use TSP to clean concrete driveway
How do I clean a concrete driveway of rust and crushed acorns? Roderick A. Matheson Sarasota, Fla.
First, try a strong solution of TSP (trisodium phosphate) and warm water. Scrub the surface thoroughly and rinse with clear water.
If the stains persist, apply a 1-to-3 solution of muriatic acid and water. Scrub the drive with a stiff-bristle brush. Allow the mixture to remain for 15 minutes, or until the bubbling action stops. Then rinse with clear water.
Keep the acid solution off plants, skin or clothing. Follow the usual precautions when using acid. Never put the acid in a metal pail or container. Add the acid to the water, not vice versa.
After the concrete is cleaned to your satisfaction, begin a maintenance program by applying a clear concrete sealer to the surface. Be mindful, however , that once you start the seal-coating procedure, you should continue it regularly.
As my Hoosier grandmother might have said: "An ounce of seal-coat prevention is better than pounding out stains with TSP or acid." Or something like that.