Cleaning Tar from Etched Concrete

What is karnac?

I think he must be referring to Karnac. I have no idea how to remove if from etched concrete though.

YES YOU HAVE THE RIGHT IDEA ABOUT KARNAC. WE HAVE TRIED ALOT OF DIFFERENT THINGS TO CLEAN THIS OFF. WE HAVE TRIED A BURNING IT OFF AND THAN CLEANING UP WHATS LEFT AND THIS DOSENT COME OUT VERY WELL.

I thought he meant...

This is the Karnak that I am aware of....

I don't know what karnac is either, or how much you're talking about.

For tar, I'll use some type of solvent to loosen it up. Mineral spirits works. Put it on the tar and scrub it. Let sit for about 10-15 minutes. Mix a strong solution of liquid dish washing soap with water in a garden sprayer. Dawn works well. Spray on affected surface..............right over the mineral spirits. Let sit another 10-15 minutes. Pressure wash with a 15° tip.

This will work to remove the tar, but I can't promise it's going to look like new concrete. There may be some stains left.

Name brand Asphalt

Burn it off with a torch, then clean it up with muriatic acid.

You could also just pour diesel fuel or kerosene on it for better affects.

Hot water pressure washer.

Mineral Spirits will dissolve both but you will have the problem of it soaking into the concrete farther staining it.

Burning it off may cause the surface to chip if it gets to hot.

There are disolvents, if that is a word, for various types of petroleum products---I do remember that TARMAC, was the word for an old asphalt air runway--Anyway--Finding an product that emulsifies, and puts the stain product into suspension, and then using the process described here, of a hot steam treatment, may be the best way--Remember to find a way to contain, and or, retrieve the disolved solution, or or will wash down and soil another part of the area--Good luck, and please post the results of whatever method you have chosen--Thanks, Mac

diethyl ether starting fluid.

Milo

Dry ice blasting is effective on tar. As on tar spreaders and other equipment associated with the asphalt paving industry. How much cleaning is there to do (square footage)? This is an important due to the set up and logistics of using dry ice blasting. A large amount of compressed air, typically at least 140 cfm, is required to operate the blasting machine. Another downside is that dry ice will not "draw" any stains out of the concrete nor will it remove any concrete that contains the stain (such as sand blasting would). The upside is that it will not do any harm to the concrete as dry ice blasting is non- abrasive by nature. Another upside is there is zero secondary cleanup or contamination. If you have enough square footage it may be your best method as it will not smear or dilute the tar during the removal process which typically causes more staining. Then a follow up with muratic acid or some other type of chemical to remove or draw any stains out.

What you want is an emulsifier that makes the tar and karnak soluable in water. There are several available but it helps if you know what to call it. Automotive hand cleaner is one example but there are other forms in a much thinner liquid form.

In the asphalt business for years we have been using a citrus base asphalt release compound. It is biodegradeable and safe to use on concrete. Different supplier can be found on the internet. If you contact me and I'll give you our supplier and msds sheets.

what we found works the best is a product called ( OOP' S ) it is sold in paint stores, the other product we found that works is a citris based hand cleaner soap. both put on for 5 minutes to soak and than useing a mediem bristle brush to scrub with. than washed off with cold water pressure washer. the hot water seemed to smear the KARNAK. thanks for all the great ideas and help.