Caution must be exercised when using acid to etch concrete due to the possible health problems and the damage it may do to plants, clothing or nearby equipment. This article will describe the basic process, but you must follow the safety instructions given to you by the seller of the product or as indicated on the label.
Hydrochloric acid which is mainly sold for brick cleaning concrete driveway new orleans will attack the lime in the concrete and dissolve the bond. When it is used on a concrete floor, driveway or pavement it is quickly neutralized or mostly neutralized on contact or when the fizzing has stopped so it only acts on the surface. Usually a mix of 10 parts of water to one part of acid will be strong enough to remove the polish from the surface. If you wear correct protective clothing, gloves and eye protection and take care not to splash, the best way to apply the acid is with a long handled paint roller with a deep pile cover. Apply it liberally and slowly enough to prevent a spray.
After applying the acid/water mix and before it dries thoroughly water jet clean the concrete by blasting it with 3,000 psi close to the concrete, rinsing is not good enough to remove the surface particles and a rotary jet (like a lawnmower) is the best way. When the concrete is dry apply the first coat of paint.
This is better left to the experts who know what power of machine to use, what size shot and how fast each pass should blast the surface. These machines throw small steel balls at the concrete within a sealed chamber by passing the shot through a fast-spinning paddle wheel. The shot hits the surface, breaks it open and then bounces back up the return chamber to be recyled while a vacuum system separates and removes the dust and grit. Shot blasting can open the surface more than intended and leave deeper grooves where the blasting overlaps so it is not ideal for home applications.
These devices come in all shapes and power sizes as well as wheel configurations, from small hand held angle grinders with a dust extraction shroud and diamond grinding wheel to large walk-behind machines that have multiple wheels underneath. For driveways that need only the edges opened at the surface an angle grinder set up as a concrete grinder is ideal. It will grind dry and the dust collector will remove all the dust as you work. For larger areas more than the edges a sit down grinder or stand up grinder using an angle grinder as the motor source will be faster and easier. There is a dust extraction shroud that even gets into the corners and most have edging features to grind against walls.
They work by using a spinning wheel in contact with the concrete that has diamond segments welded to the wheel. As these diamonds come in contact with the concrete they wear away and grind off the top surface. The dust extraction shroud contains all the dust and the dust collector removes it without airborne particles.
Once your surface is open and clean apply the first coat thinned 10% to soak into the surface as deeply as possible. If your preparation is good it will look dull and lifeless when it has dried. Depending on the coating, apply another coat once the first has fully dried which will give you a glossy, uniform finish. Apply a third coat if a greater thickness is required for better wear.